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OM642 Gl350 Bluetec High oil consumption diagnosis and solution
Hi all, I don't post much but thought this would be some good info for those with high oil consumption issues.
It's long so if you want to see the solution just scroll to the bottom.
The back story:
We picked up our GL350 a couple years back with about 90k on the clock. I have no idea what the service history was before we purchased it. I knew when I purchased it there was a slight oil leak from the valley weep hole indicating cooler seals starting to leak. I am a mechanic and machinist and so that oil leak did not scare me at all, having done my research and knowing what it takes to fix the problem. The leak did not get bad enough to do the cooler seals until about 105k miles. So I did the seals, replaced the oil cooler while in there and some other miscellaneous while were here type stuff. All was good until about 110k where a random out of the blue engine light and limp mode happened. This turned out to be a DPF code for regen frequency and a clogged DPF. So I pulled the DPF off and cleaned it out. All seemed good for a couple months until a routine dipstick check showed oil off the bottom of the range, so not thinking much of it I put the 2 quarts in it that it takes to be back up to full, and proceeded to check it a couple weeks later only to find it low again... so the search began to find where the oil was going. This went on for about 5k miles until I started to get serious about solving the oil consumption issue.
So first, check the PCV valve on the back of the pass side head. I could not find anything wrong with it but I put a new one on anyway. the old one did show lots of oil and there was considerable amounts of oil at the turbo inlet. This had no change on the oil consumption issue. Next, turbo. The turbo showed some signs of wear, indicated buy some rub marks from the compressor wheel on the housing. This is typically indicating the bearings are worn and so I replaced the center cartridge thinking I might have found the oil consumption issue as bad turbo bearings, and seals will leak oil into either the intake or exhaust. But no joy, oil consumption was as bad as ever and getting worse.
Good news was the engine light was staying off and as long as we kept the oil full we kept running it.
Then the DPF clogged again, as it was obvious the oil consumption was going out the exhaust this made sense, so off it came and got washed out again. But the oil use was getting worse, now at just over 120k it was getting to the point of dpf regen issues again as it could not handle the oil burn. We fought with that for another couple thousand miles until we are here at 125k oil consumption is so high its not reliable, Engine light is perma on. Oil burn is about 1 qt 150ish miles. Time to do some real diagnostics.
Just because I know someone will ask. Since I have owned it all oil changes were done at 6-8k miles and only 3 oil brands were used all with the 229.52 spec, Mobil 1, MB branded, and Liqui moly.
The Diagnosis:
First I did the scan tool compression test, which showed low compression on #2 and #5. Not being a big believer in computer diagnostics for that I went straight to Leak down test. This showed #2 as the worst at around 20% or 80% blow by all coming out the PCV vent. #5 was not quite as bad but not good as was #1. Borescope down the injector hole showed nothing bad except a bunch of oil on the top side of the piston, I could still see the cross hatch and no scoring on the cylinder. So I thought well its got ring issues, time to pull it apart and maybe I can just ball hone the cylinders and put new rings on. Keep in mind it started and ran perfect.
Out it came, yes in the GL it comes out the top pretty easy.
It's a complicated engine compartment but not that bad to get out.
Tore it down , and yep all the oil control rings were completly packed with carbon and stuck in the grooves on the pistons. I actually happy at that point, all the cylinders looked good, no scoring or bad wear, bearings looked like new on both the rods and mains, so I thought hone the cylinders and put new rings in, it will be good..... Then I got the measuring tools out and that is where it went down hill. The cylinders all measured right at the limit for out of round and size except #5, that one was bad, out of round was .002" or .050mm out of round at the top. MB spec max out of round is .0007mm. Then I took a look at the heads, and all the exhaust valve stems look terrible at the rocker and the rockers match, also the lifters look terrible where the ride in the heads... so it needs heads redone...
So after pricing out all the parts and machine shop labor to bore, hone, refresh the heads with new valves, lifters, rockers etc. the cost would be somewhere around $6000 to $6500. And then I needed to assemble and put it back in. This is a totally doable option but I thought let me see what is out there for engines....
The Solution:
As some of you know the price for used OM642 engines is somewhat rediculous or even stupid these things are not made of gold, and I'm not paying 6-8K for a engine with 150k+ miles on it that may have the same problems or develop them in a couple thousand miles. I don't know who is buying these used engines for that much or if they are not selling, but you would think if the salvage yards were not getting that $ they would lower the price. Anyway I found a couple reman shops offering rebuilt engines for between $7500 and $8000, this sounded like a good plan at this point due to warranty offerings from both, but some searching online returned more bad reviews than I was willing to dismiss and decided this is not the way to go.
So out of just pure curiosity I called my local MB dealer...
IF you have read this far here's the best option:
GET A REMAN straight from MB!! The basic engine, is what they call it. It comes as a long block, meaning you will need to swap your accessories, intake manifolds, exhaust manifolds, Turbo, wire harnesses, injector lines, and all other little stuff that bolts on the top. But it comes with new injectors, glow plugs, oil cooler, sensors in the pan, cam sensor, oil pan, turbo pedestal, oil filter housing, water outlet neck and lifting eyes. 4yr 50k mile warranty and is stood behind by MB. This thing is more new than reman though, the heads and block are definetly new as is the oil filter housing and injectors, and glow plugs. the only parts I can verify that are not new is the oil pan and front timing cover.
Best of all.... Came in at right around $8K. This price will vary depending on your dealer. I know that is not chump change, but lets be real here, I could rebuild mine at a cost of $6500 + my labor. and if I screw something up or have a problem it's all on me, the parts are not cheap and one minor problem can be expensive. And that does not include new injectors. Just the injectors cover the $1500 difference. Its a no brainer.
They do want the core back at a core cost of $3200 so keep that in mind.
OH comes with the motor supports that the grey goo leaks out of too..
Sorry for the super long post, but I know I did a ton of searching when I started down this path, and this information would have saved me some time. I hope It helps someone else diagnose and solve there problem.
I just unpacked the new engine today so it will be a little while before I get it all back together.
-Dave
Hi all, I don't post much but thought this would be some good info for those with high oil consumption issues.
It's long so if you want to see the solution just scroll to the bottom.
The back story:
We picked up our GL350 a couple years back with about 90k on the clock. I have no idea what the service history was before we purchased it. I knew when I purchased it there was a slight oil leak from the valley weep hole indicating cooler seals starting to leak. I am a mechanic and machinist and so that oil leak did not scare me at all, having done my research and knowing what it takes to fix the problem. The leak did not get bad enough to do the cooler seals until about 105k miles. So I did the seals, replaced the oil cooler while in there and some other miscellaneous while were here type stuff. All was good until about 110k where a random out of the blue engine light and limp mode happened. This turned out to be a DPF code for regen frequency and a clogged DPF. So I pulled the DPF off and cleaned it out. All seemed good for a couple months until a routine dipstick check showed oil off the bottom of the range, so not thinking much of it I put the 2 quarts in it that it takes to be back up to full, and proceeded to check it a couple weeks later only to find it low again... so the search began to find where the oil was going. This went on for about 5k miles until I started to get serious about solving the oil consumption issue.
So first, check the PCV valve on the back of the pass side head. I could not find anything wrong with it but I put a new one on anyway. the old one did show lots of oil and there was considerable amounts of oil at the turbo inlet. This had no change on the oil consumption issue. Next, turbo. The turbo showed some signs of wear, indicated buy some rub marks from the compressor wheel on the housing. This is typically indicating the bearings are worn and so I replaced the center cartridge thinking I might have found the oil consumption issue as bad turbo bearings, and seals will leak oil into either the intake or exhaust. But no joy, oil consumption was as bad as ever and getting worse.
Good news was the engine light was staying off and as long as we kept the oil full we kept running it.
Then the DPF clogged again, as it was obvious the oil consumption was going out the exhaust this made sense, so off it came and got washed out again. But the oil use was getting worse, now at just over 120k it was getting to the point of dpf regen issues again as it could not handle the oil burn. We fought with that for another couple thousand miles until we are here at 125k oil consumption is so high its not reliable, Engine light is perma on. Oil burn is about 1 qt 150ish miles. Time to do some real diagnostics.
Just because I know someone will ask. Since I have owned it all oil changes were done at 6-8k miles and only 3 oil brands were used all with the 229.52 spec, Mobil 1, MB branded, and Liqui moly.
The Diagnosis:
First I did the scan tool compression test, which showed low compression on #2 and #5. Not being a big believer in computer diagnostics for that I went straight to Leak down test. This showed #2 as the worst at around 20% or 80% blow by all coming out the PCV vent. #5 was not quite as bad but not good as was #1. Borescope down the injector hole showed nothing bad except a bunch of oil on the top side of the piston, I could still see the cross hatch and no scoring on the cylinder. So I thought well its got ring issues, time to pull it apart and maybe I can just ball hone the cylinders and put new rings on. Keep in mind it started and ran perfect.
Out it came, yes in the GL it comes out the top pretty easy.
It's a complicated engine compartment but not that bad to get out.
Tore it down , and yep all the oil control rings were completly packed with carbon and stuck in the grooves on the pistons. I actually happy at that point, all the cylinders looked good, no scoring or bad wear, bearings looked like new on both the rods and mains, so I thought hone the cylinders and put new rings in, it will be good..... Then I got the measuring tools out and that is where it went down hill. The cylinders all measured right at the limit for out of round and size except #5, that one was bad, out of round was .002" or .050mm out of round at the top. MB spec max out of round is .0007mm. Then I took a look at the heads, and all the exhaust valve stems look terrible at the rocker and the rockers match, also the lifters look terrible where the ride in the heads... so it needs heads redone...
So after pricing out all the parts and machine shop labor to bore, hone, refresh the heads with new valves, lifters, rockers etc. the cost would be somewhere around $6000 to $6500. And then I needed to assemble and put it back in. This is a totally doable option but I thought let me see what is out there for engines....
The Solution:
As some of you know the price for used OM642 engines is somewhat rediculous or even stupid these things are not made of gold, and I'm not paying 6-8K for a engine with 150k+ miles on it that may have the same problems or develop them in a couple thousand miles. I don't know who is buying these used engines for that much or if they are not selling, but you would think if the salvage yards were not getting that $ they would lower the price. Anyway I found a couple reman shops offering rebuilt engines for between $7500 and $8000, this sounded like a good plan at this point due to warranty offerings from both, but some searching online returned more bad reviews than I was willing to dismiss and decided this is not the way to go.
So out of just pure curiosity I called my local MB dealer...
IF you have read this far here's the best option:
GET A REMAN straight from MB!! The basic engine, is what they call it. It comes as a long block, meaning you will need to swap your accessories, intake manifolds, exhaust manifolds, Turbo, wire harnesses, injector lines, and all other little stuff that bolts on the top. But it comes with new injectors, glow plugs, oil cooler, sensors in the pan, cam sensor, oil pan, turbo pedestal, oil filter housing, water outlet neck and lifting eyes. 4yr 50k mile warranty and is stood behind by MB. This thing is more new than reman though, the heads and block are definetly new as is the oil filter housing and injectors, and glow plugs. the only parts I can verify that are not new is the oil pan and front timing cover.
Best of all.... Came in at right around $8K. This price will vary depending on your dealer. I know that is not chump change, but lets be real here, I could rebuild mine at a cost of $6500 + my labor. and if I screw something up or have a problem it's all on me, the parts are not cheap and one minor problem can be expensive. And that does not include new injectors. Just the injectors cover the $1500 difference. Its a no brainer.
They do want the core back at a core cost of $3200 so keep that in mind.
OH comes with the motor supports that the grey goo leaks out of too..
Sorry for the super long post, but I know I did a ton of searching when I started down this path, and this information would have saved me some time. I hope It helps someone else diagnose and solve there problem.
I just unpacked the new engine today so it will be a little while before I get it all back together.
-Dave
Great post! Please update when the new mill is purring.
What do you think caused the problem, and how will you avoid it on the new engine?
That's the million dollar question. I don't know what caused it I can only assume a couple things: 1. The emission system on these engines is harmful to there life.. the egr puts soot back into the intake tract and cylinders and the regen cycle of the DPF over fuels the cylinders. This snowballs as the engine starts to consume some oil and then the regen cycles happen more and more often pushing more fuel past the rings into the oil. I don't think the low Low SPAsh oil is the best oil to handle the fuel contamination and deal with the soot from the egr. But It is designed to help reduce DPF issues.
With that being said I think 2 things may have been major contributors to what happened in my engine.
1. previous owner may not have done proper maintenance or pushed the maintenance out past the recommended time (for the record I don't think 10k oil changes in this engine are a good thing at all) This may have started the down hill slide.
2. Our driving style/ trip distance changed. When we first got the GL we did more trips and highway driving mixed with local driving. But right around when we first started to notice the oil consumption going up we had changed to more local driving and less highway driving. I do believe that is not ideal for these vehicles... actually not ideal for the emission systems.
To combat the issues with the new engine I am planning on looking at different oils, but that's a rabbit hole in itself. Plus I have to be careful to maintain the warranty on the new engine from MB as they want oil and filter documentation for any warranty claim, that includes oil brand and weight, and filter brand.
We are going to change the use of this vehicle so it sees more highway miles on a regular basis.
I will continue to do more often oil changes, probably in the 5-6k mile range and do some oil analysis here and there to see what is going on with the oil and adjust the drain frequency based on that.
I am going to have MB do the emission system update because I do believe there is a change in the calibration for the regen cycle that helps reduce the time and or frequency which will reduce the fuel contamination in the oil.
I am also planing on running some DPF additives to the fuel, they typically reduce the temperature needed to regen and can help with passive regen and reduce the active regen frequency.
After that I may consider some aftermarket programing to remove the egr/dpf issues but I don't know yet. I would like to avoid this for now as after the MB update the car will have a new dpf and sensors and some extended warranty on the emissions system.
Honest reality is If it makes it another 125k it will probably be time to move on from this vehicle.
What do you think caused the problem, and how will you avoid it on the new engine?
That is the million dollar question.
1. I don't know what the service history was before me.
2. Our driving switched from highway/local to mostly local around 110k
I believe the entire problem is emission system caused. Not because it does not work, but because it does, and between the EGR putting soot back into the intake/cylinders and the Regen cycle dumping excess fuel in the cylinders and washing past the rings into the oil.
We will be doing the emissions update once it is released for the 164 chassis, I have heard that the recalibration does modify the regen cycle to lower the frequency and amount of fuel, so that may help.
I am also going to be running some dpf cleaner additive in the fuel on a regular basis to help with passive regen.
I am going to do some more research on oil and do oil analysis on a regular basis and adjust the drain interval according to the analysis.
That is the plan for now, but the reality is if it lasts for another 125k it will probably be time to move on from this vehicle before then.
-Dave
Was the piston you pictured typical of all of them? The oil appears to have gelled in the ring area, and the oil ring area seems to have been very hot. I wonder if the engine had been overheated before you bought it. The oil rings might have lost their spring or temper, making them easy to stick. Of course I am no expert and find the gunked up piston very puzzling. Oil experts might be able to tell what went wrong from the piston picture.
Yea, all the pistons look similar. I do not think or have any reason to believe it was overheated. The Oil control rings are a hollow u shaped ring with slots in it, behind it is a spring. They were totally packed with carbon and stuck in the groove effectively letting oil get sucked up past them. I cleaned up one and the control rings are fine. In order for those rings to get hot enough to change there temper there would have been obvious other heat related damage to the piston. being as they are the farthest down from the top. Also this engine runs oil squirters to cool the bottom of the piston. I truly believe that it is caused by the combination of regen cycles, and egr (partly due to our around town use and probably some pre existing condition before we purchased the vehicle) This caused carbon to pack in the rings and cause lots of oil on top of the piston. The reason they look so bad is due to that excessive oil on top of the piston that does not burn completely and ends up on the sides of the piston and in the rings.
Are you familiar with the Peachparts Mercedes Benz forums diesel section? This is a hang out for the diesel mechanical types who might have ideas about what happened and how to avoid it. It is also a good place for Mercedes parts.
Hi all, I don't post much but thought this would be some good info for those with high oil consumption issues.
It's long so if you want to see the solution just scroll to the bottom.
The back story:
We picked up our GL350 a couple years back with about 90k on the clock. I have no idea what the service history was before we purchased it. I knew when I purchased it there was a slight oil leak from the valley weep hole indicating cooler seals starting to leak. I am a mechanic and machinist and so that oil leak did not scare me at all, having done my research and knowing what it takes to fix the problem. The leak did not get bad enough to do the cooler seals until about 105k miles. So I did the seals, replaced the oil cooler while in there and some other miscellaneous while were here type stuff. All was good until about 110k where a random out of the blue engine light and limp mode happened. This turned out to be a DPF code for regen frequency and a clogged DPF. So I pulled the DPF off and cleaned it out. All seemed good for a couple months until a routine dipstick check showed oil off the bottom of the range, so not thinking much of it I put the 2 quarts in it that it takes to be back up to full, and proceeded to check it a couple weeks later only to find it low again... so the search began to find where the oil was going. This went on for about 5k miles until I started to get serious about solving the oil consumption issue.
So first, check the PCV valve on the back of the pass side head. I could not find anything wrong with it but I put a new one on anyway. the old one did show lots of oil and there was considerable amounts of oil at the turbo inlet. This had no change on the oil consumption issue. Next, turbo. The turbo showed some signs of wear, indicated buy some rub marks from the compressor wheel on the housing. This is typically indicating the bearings are worn and so I replaced the center cartridge thinking I might have found the oil consumption issue as bad turbo bearings, and seals will leak oil into either the intake or exhaust. But no joy, oil consumption was as bad as ever and getting worse.
Good news was the engine light was staying off and as long as we kept the oil full we kept running it.
Then the DPF clogged again, as it was obvious the oil consumption was going out the exhaust this made sense, so off it came and got washed out again. But the oil use was getting worse, now at just over 120k it was getting to the point of dpf regen issues again as it could not handle the oil burn. We fought with that for another couple thousand miles until we are here at 125k oil consumption is so high its not reliable, Engine light is perma on. Oil burn is about 1 qt 150ish miles. Time to do some real diagnostics.
Just because I know someone will ask. Since I have owned it all oil changes were done at 6-8k miles and only 3 oil brands were used all with the 229.52 spec, Mobil 1, MB branded, and Liqui moly.
The Diagnosis:
First I did the scan tool compression test, which showed low compression on #2 and #5. Not being a big believer in computer diagnostics for that I went straight to Leak down test. This showed #2 as the worst at around 20% or 80% blow by all coming out the PCV vent. #5 was not quite as bad but not good as was #1. Borescope down the injector hole showed nothing bad except a bunch of oil on the top side of the piston, I could still see the cross hatch and no scoring on the cylinder. So I thought well its got ring issues, time to pull it apart and maybe I can just ball hone the cylinders and put new rings on. Keep in mind it started and ran perfect.
Out it came, yes in the GL it comes out the top pretty easy.
It's a complicated engine compartment but not that bad to get out.
Tore it down , and yep all the oil control rings were completly packed with carbon and stuck in the grooves on the pistons. I actually happy at that point, all the cylinders looked good, no scoring or bad wear, bearings looked like new on both the rods and mains, so I thought hone the cylinders and put new rings in, it will be good..... Then I got the measuring tools out and that is where it went down hill. The cylinders all measured right at the limit for out of round and size except #5, that one was bad, out of round was .002" or .050mm out of round at the top. MB spec max out of round is .0007mm. Then I took a look at the heads, and all the exhaust valve stems look terrible at the rocker and the rockers match, also the lifters look terrible where the ride in the heads... so it needs heads redone...
So after pricing out all the parts and machine shop labor to bore, hone, refresh the heads with new valves, lifters, rockers etc. the cost would be somewhere around $6000 to $6500. And then I needed to assemble and put it back in. This is a totally doable option but I thought let me see what is out there for engines....
The Solution:
As some of you know the price for used OM642 engines is somewhat rediculous or even stupid these things are not made of gold, and I'm not paying 6-8K for a engine with 150k+ miles on it that may have the same problems or develop them in a couple thousand miles. I don't know who is buying these used engines for that much or if they are not selling, but you would think if the salvage yards were not getting that $ they would lower the price. Anyway I found a couple reman shops offering rebuilt engines for between $7500 and $8000, this sounded like a good plan at this point due to warranty offerings from both, but some searching online returned more bad reviews than I was willing to dismiss and decided this is not the way to go.
So out of just pure curiosity I called my local MB dealer...
IF you have read this far here's the best option:
GET A REMAN straight from MB!! The basic engine, is what they call it. It comes as a long block, meaning you will need to swap your accessories, intake manifolds, exhaust manifolds, Turbo, wire harnesses, injector lines, and all other little stuff that bolts on the top. But it comes with new injectors, glow plugs, oil cooler, sensors in the pan, cam sensor, oil pan, turbo pedestal, oil filter housing, water outlet neck and lifting eyes. 4yr 50k mile warranty and is stood behind by MB. This thing is more new than reman though, the heads and block are definetly new as is the oil filter housing and injectors, and glow plugs. the only parts I can verify that are not new is the oil pan and front timing cover.
Best of all.... Came in at right around $8K. This price will vary depending on your dealer. I know that is not chump change, but lets be real here, I could rebuild mine at a cost of $6500 + my labor. and if I screw something up or have a problem it's all on me, the parts are not cheap and one minor problem can be expensive. And that does not include new injectors. Just the injectors cover the $1500 difference. Its a no brainer.
They do want the core back at a core cost of $3200 so keep that in mind.
OH comes with the motor supports that the grey goo leaks out of too..
Sorry for the super long post, but I know I did a ton of searching when I started down this path, and this information would have saved me some time. I hope It helps someone else diagnose and solve there problem.
I just unpacked the new engine today so it will be a little while before I get it all back together.
-Dave
oh man oh man, this is one post that answered all my questions about my GL350 burning oil excessively. I had the MB Diesel Settlement AEM done on my GL March 2021, car started to burn oil excessively, dealer did oil consumption test and it failed it, dealer put on a new turbo ( Fletcher Jones MB Newport Beach) since then it still burns oil excessively, did another oil consumption test Oct 2021 and it came out 0.1 away from failing it so dealer could not do anything about replacing the engine. Now, due to all this oil burn I get engine check light and limp mode, - they are replacing a DPF now ( under warranty through diesel class action lawsuit ) BUT I am afraid DPF will be dirty again in just few thousand miles due to oil being thrown down to DPF. I think I will do another oil consumption test (3rd one ) vehicle is still under MB extended warranty so after 3rd oil consumption test and if they don’t fix it - I think I will be calling a lemon law attorney
I love your story with getting remanifactured engine from MB dealer! Where are you located at? May be I should call your MB dealer to get a new engine!
oh man oh man, this is one post that answered all my questions about my GL350 burning oil excessively. I had the MB Diesel Settlement AEM done on my GL March 2021, car started to burn oil excessively, dealer did oil consumption test and it failed it, dealer put on a new turbo ( Fletcher Jones MB Newport Beach) since then it still burns oil excessively, did another oil consumption test Oct 2021 and it came out 0.1 away from failing it so dealer could not do anything about replacing the engine. Now, due to all this oil burn I get engine check light and limp mode, - they are replacing a DPF now ( under warranty through diesel class action lawsuit ) BUT I am afraid DPF will be dirty again in just few thousand miles due to oil being thrown down to DPF. I think I will do another oil consumption test (3rd one ) vehicle is still under MB extended warranty so after 3rd oil consumption test and if they don’t fix it - I think I will be calling a lemon law attorney
I love your story with getting remanifactured engine from MB dealer! Where are you located at? May be I should call your MB dealer to get a new engine!
Unfortunately you are a long way from my dealer. I am In PA and use Tom Masano Mercedes in Reading Pa. They are a good dealer with a great parts department. It is a real shame that there are some good dealers and some not so good dealers. I would say if the oil consumption is bad enough to clog the dpf that MB should replace or repair the engine if it is under waranty. Do you have a different dealer close to you you could try? What year is your GL and how many miles on it? How much oil does it use?
Keep in mind that I did all the labor on the engine swap myself so It only cost me the parts. This kept the total cost of the engine and misc parts I needed to change it out under 9k. It is now at the dealer having the AEM done so once i get it back it should be all good for a long time.
Good topic. I would compare it to "seized engine" topic, where members reported several cases where lower grade oils used on OM642 cost them to turn into gelatin.
I don't see MY of GL posted here, but is it DEF equipped. or earlier model?
Either way, I strongly advise any Bluetec owner to buy monitoring scanner like ScanGauge and monitor DPF regenerations as that is dark hole who can lead to lot of troubles.
When it comes to oils, I always follow MB computers. Just did oil change on my OM651 Bluetec and after 11k miles/2 years the Blackstone tells me I could go for 13k miles intervals.
Good topic. I would compare it to "seized engine" topic, where members reported several cases where lower grade oils used on OM642 cost them to turn into gelatin.
I don't see MY of GL posted here, but is it DEF equipped. or earlier model?
Either way, I strongly advise any Bluetec owner to buy monitoring scanner like ScanGauge and monitor DPF regenerations as that is dark hole who can lead to lot of troubles.
When it comes to oils, I always follow MB computers. Just did oil change on my OM651 Bluetec and after 11k miles/2 years the Blackstone tells me I could go for 13k miles intervals.
My GL is a 2010 DPF (its at mercedes right now to get the AEM done so it's getting a new one.) and while I agree some cases of improper oil cause damage, in my engine the bearings looked perfect. I believe in every case of oil jello there was a underlying problem that caused it more than the oil. The regen cycle dumping fuel past the rings and extended oil changes can cause it. the problem is with these vehicles there is no information on regen cycles or any indication to the average driver that it is happening. I believe it gets to the point of some unfortunate series of circumstances that causes a bunch of regen cycles and this degrades the oil. There is a engine fault code for regen cycle frequency not ok. Mercedes says this means it is happening too often and it should be diagnosed, but they say change oil immediately with this code, so they know it is damaging to the oil.
I do plan on doing regular oil analysis on this new engine, once I get it back i'm doing the first oil change at 1k and then I will send out a sample at the next 3k mark just to make sure everything is behaving itself. then 5k and go on recommendations from analysis. But I don't think i will ever run 10k changes. probably in the 8k range.
Unfortunately you are a long way from my dealer. I am In PA and use Tom Masano Mercedes in Reading Pa. They are a good dealer with a great parts department. It is a real shame that there are some good dealers and some not so good dealers. I would say if the oil consumption is bad enough to clog the dpf that MB should replace or repair the engine if it is under waranty. Do you have a different dealer close to you you could try? What year is your GL and how many miles on it? How much oil does it use?
Keep in mind that I did all the labor on the engine swap myself so It only cost me the parts. This kept the total cost of the engine and misc parts I needed to change it out under 9k. It is now at the dealer having the AEM done so once i get it back it should be all good for a long time.
Great to hear you are able to take advantage of the AEM, I read many posters chose to sell their diesel MB right after AEM with its emissions warranty.
my GL is a 2016 GL350. It started to burn oil right after AEM was done at 160,000, . which is probably not related judging by numerous posts about excessive oil consumptions in diesel GL's right now I have 197,000 miles on it and about 10,000 miles left on that AEM emissions warranty. it burns 2 quarts every 1,000 - 1,200 miles. At this point I have decided to try another MB dealer here for another oil consumption test, if that doesn't get me a new engine, I will go a lemon law attorney route (1+ years left on unlimited mile extended warranty). and 3rd last option will be following your example of buying a remanufactured engine from MB and will either do it myself or ask a friend to help out, its better than selling the car for pennies. It still has great body and excellent interior and absolutely nothing else wrong with it. These are great cars, its a shame I will never ever will be buying a Mercedes Benz vehicle ever again.
Great to hear you are able to take advantage of the AEM, I read many posters chose to sell their diesel MB right after AEM with its emissions warranty.
my GL is a 2016 GL350. It started to burn oil right after AEM was done at 160,000, . which is probably not related judging by numerous posts about excessive oil consumptions in diesel GL's right now I have 197,000 miles on it and about 10,000 miles left on that AEM emissions warranty. it burns 2 quarts every 1,000 - 1,200 miles. At this point I have decided to try another MB dealer here for another oil consumption test, if that doesn't get me a new engine, I will go a lemon law attorney route (1+ years left on unlimited mile extended warranty). and 3rd last option will be following your example of buying a remanufactured engine from MB and will either do it myself or ask a friend to help out, its better than selling the car for pennies. It still has great body and excellent interior and absolutely nothing else wrong with it. These are great cars, its a shame I will never ever will be buying a Mercedes Benz vehicle ever again.
With that level of oil consumption I can't see why MB would not do something about it. What are they telling you the acceptable range is for oil use? They know that with that much oil use the DPF will not handle it. Hopefully the other dealer will be of better help with your issue.
My question is why the cylinders are so far out of round? Once that happens, there's no way the rings can seal effectively...
Don't know if Futureal's problem is the same or not. One issue that seems to be cropping up all over the industry is the use of lower tension rings, especially in the oil control ring, for less friction. Eventually, the passages in the piston that allow the oil to return to the crankcase get clogged and the rings end up skating over the oil film, effectively pumping it to the top of the piston where it burns, after a fashion.
Ugh.. .Stephens is full of it. He tells a good story and sucks you in, but the truth is most of his information is wrong at best and misleading for sure. He dose have a couple pieces of decent info but its mostly blown out of proportion and hidden in his ranting. He is just a old guy who does not like modern diesel tech. If you believed his ranting all of these engines would be blown up at 60k miles. NO just NO. His page falls under the if you read it on the internet it must be true....
My question is why the cylinders are so far out of round? Once that happens, there's no way the rings can seal effectively...
Don't know if Futureal's problem is the same or not. One issue that seems to be cropping up all over the industry is the use of lower tension rings, especially in the oil control ring, for less friction. Eventually, the passages in the piston that allow the oil to return to the crankcase get clogged and the rings end up skating over the oil film, effectively pumping it to the top of the piston where it burns, after a fashion.
It's a good question and I'm not sure what caused it in this engine, but it was only 1 cylinder that was bad enough to not be useable. I do believe that cylinder was like that for a while due to the wear pattern on the cylinder wall right at the top. funny thing is when doing compression and leakdown that one did not come up as the worst one. The oil control rings in these engines are pretty delicate but I don't think the rings are the problem. I believe the driving characteristics of a passenger car and the regen cycles of the emission system is what causes the rings to get caked with carbon and oil sludge and eventually causes them to get stuck in the ring lands on the pistons. Once this happens it just starts pumping oil. I have heard various rummers from several people who should know that MB changed the programming to help lessen this effect. The problem is most wont get this software unless they have the emissions update done. I should have mine back next week, but as these vehicles don't have any indicator on the dash to tell you its doing a regen there is really no good way to track it and see how often it happens.
, but as these vehicles don't have any indicator on the dash to tell you its doing a regen there is really no good way to track it and see how often it happens.
Even $50 scanner will give you regeneration history, although I hate the small screens.
This is history on technician computer for my Sprinter. Regeneration happens every 900 km (600) miles, unless other parameters will interrupt regural running.
these vehicles don't have any indicator on the dash to tell you its doing a regen there is really no good way to track it and see how often it happens.
I've been told that this device can monitor regen cycles and also DEF level, at least on some cars.
Even $50 scanner will give you regeneration history, although I hate the small screens.
This is history on technician computer for my Sprinter. Regeneration happens every 900 km (600) miles, unless other parameters will interrupt regural running.
yes I know the data is available via a scan tool, but that does not help the average person or even the advanced person unless you are going to drive around with the scan tool plugged in all the time. Here's the scenario: sburban family, car or suv gets driven as a run around town vehicle, the time to get it warmed up to and all parameters in range to do a regen, the regen starts, but wait they are at there destination so it gets shut down. 1 hr later they get back in the vehicle and drive the same distance home guess what it trys to complete the regen but didn't get it done because the vehicle was not on long enough. this continues throughout the week or weekend ant then maybe it gets driven farther and completes the cycle. By doing this the oil gets a bunch of fuel contamination from the 4 or 5 half failed regen cycles and this starts to snowball until one day Mary is diving down the highway and it locks up and no one knows why because they serviced it at the dealer every 10k miles. But If there was a dash indicator that said it was doing a regen and the message indicator said something like "regen in process keep driving until complete" the cycle would finish and the oil would not be contaminated and the engine would last. Now I know not everyone would follow this indicator but I would and would tell the wife about it and she would do it also. As this cycle happens the cylinders get washed down more and more leading to oil consumption, leading to more regens (that don't complete due to short trip) and you see what happens.
Those with sprinters typically don't short trip as much and between that and heavier loads on the engine (warms up quicker) does not get as many failed regen cycles. I also believe the programming is different for the regen as it is on passenger cars.
yes I know the data is available via a scan tool, but that does not help the average person or even the advanced person unless you are going to drive around with the scan tool plugged in all the time..........
This is what I have been doing with my ScanGauge for years.
Regeneration monitoring is crucial in our sedan, who is used for city driving on distances of 3-10 miles.
When I see the regeneration pending when I am getting close to my destination, I just take another loop around city block.
Once my wife aborted regeneration coming home. Following day I took the car and regeneration resume once the engine reached 60C. Took about 5 miles of street driving to accomplish. Strange that car still does ECO stop with pending regeneration, so I turn ECO off in such moment.
Aborting regeneration once or twice in the row is not big deal, but common experience is that when you do it 3 times in the row, the particle buildup will exceed self-regeneration limits, CEL will light and since some owners tend to ignore CEL when the vehicle still drives good, that can lead to limp mode and whole hell broken loose.
ScanGauge is not cheap for what it is, but sure beats alternative.
With that level of oil consumption I can't see why MB would not do something about it. What are they telling you the acceptable range is for oil use? They know that with that much oil use the DPF will not handle it. Hopefully the other dealer will be of better help with your issue.
I spoke to foreman at Fletcher Jones Mercedes here in Newport Beach, we did another oil consumption test and official number is 970ml per 1,000km which is way excessive. He said the normal is 800ml per 1,000 km tops. I asked for engine replacement, HE will request with extended warranty and Mercedes hope they approve it. If they don't Pacific Benz here in Costa Mesa, CA quoted me $9500 for long block with shipping and $2700 for labor and 7 days to everything for reman engine with 100,000 mile warranty.
They way i see it if i don't get the engine replaced I will need a new DPF filter in 6 months or so, and my AEM Emssions Warranty will probably expire by then because we all get I think 48,000 miles warranty on AEM components.
These cars a great, wish they didn't have all these problems, poorly thought-out DPF regen process with lack of any indication that it is happening.
It's a good question and I'm not sure what caused it in this engine, but it was only 1 cylinder that was bad enough to not be useable. I do believe that cylinder was like that for a while due to the wear pattern on the cylinder wall right at the top. funny thing is when doing compression and leakdown that one did not come up as the worst one. The oil control rings in these engines are pretty delicate but I don't think the rings are the problem. I believe the driving characteristics of a passenger car and the regen cycles of the emission system is what causes the rings to get caked with carbon and oil sludge and eventually causes them to get stuck in the ring lands on the pistons. Once this happens it just starts pumping oil. I have heard various rummers from several people who should know that MB changed the programming to help lessen this effect. The problem is most wont get this software unless they have the emissions update done. I should have mine back next week, but as these vehicles don't have any indicator on the dash to tell you its doing a regen there is really no good way to track it and see how often it happens.
Hi.
Very interesting thread, thank you.
A question if i may?
I have the OM642 in my Jeep but it looks very different to yours. What is the big 'lump' underneath the crank pulley? Is that a sump? My OM642 has nothing like that.
My Jeep does not have a DPF. Given regular oil changes will mine be free of these wear issues? I never go beyond 5000 miles between changes.
2013 ML350 Bluetec, 1966 Ford Mustang Convertible (sold)
Originally Posted by Futureal
Great to hear you are able to take advantage of the AEM, I read many posters chose to sell their diesel MB right after AEM with its emissions warranty.
my GL is a 2016 GL350. It started to burn oil right after AEM was done at 160,000, . which is probably not related judging by numerous posts about excessive oil consumptions in diesel GL's right now I have 197,000 miles on it and about 10,000 miles left on that AEM emissions warranty. it burns 2 quarts every 1,000 - 1,200 miles. At this point I have decided to try another MB dealer here for another oil consumption test, if that doesn't get me a new engine, I will go a lemon law attorney route (1+ years left on unlimited mile extended warranty). and 3rd last option will be following your example of buying a remanufactured engine from MB and will either do it myself or ask a friend to help out, its better than selling the car for pennies. It still has great body and excellent interior and absolutely nothing else wrong with it. These are great cars, its a shame I will never ever will be buying a Mercedes Benz vehicle ever again.
Thanks for sharing your experience. This is very scary to read for me. My 2013 ML350 is at 250 000 km (around 155 000 miles) with a full delete and it runs perfectly (except the front collision radar that seems busted). It doesn't burn any oil. In Canada, we will be getting the AEM letters soon to schedule appointments to install the new parts. I'm really debating whether to go with the AEM or just stick with my delete... decisions decisions...
12-27-2021, 09:13 PM
