2006-2012 W164 - Successful Front Differential Rebuild
11-29-2013, 10:01 AM
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2006-2012 W164 - Successful Front Differential Rebuild
Gentlemen!
I have successfully rebuilt my 2006 ML500 front differential and would like to share my experience with you!
I am a licensed/certified mechanic with experience in rebuilding diffs. I must say that doing this job is easy and any qualified/experienced mechanic should be able to handle it with ease. It would be a difficult task for a DIY’er, but not impossible.
Tools required:
Cause of Failure:
In my personal professional opinion the cause of pre-mature failure is due to three reasons:
Original OEM Set: http://www.ebay.com/itm/2006-12-Mercedes-ML-W164-Front-Diff-Bearings-Hard-To-Find-Not-Sold-in-USA-/121224489131?hash=item1c398ae8ab&vxp=mtr
Hope this helps someone out there.
Cheers!
I have successfully rebuilt my 2006 ML500 front differential and would like to share my experience with you!
I am a licensed/certified mechanic with experience in rebuilding diffs. I must say that doing this job is easy and any qualified/experienced mechanic should be able to handle it with ease. It would be a difficult task for a DIY’er, but not impossible.
Tools required:
- 36mm impact socket for spindle nuts <li itxtHarvested="0" itxtNodeId="33">32mm impact socket for diff pinion nut
- Torx bit for front drive shaft bolt
- Assorted wrenches and socets
- 12 ton shop press
- Oxy-Acetylene torch (or other adequate heat source)
- Air hammer
- Compressor and Impact Wrench
- Torque Wrench - Click type ft/lbs and analog needle type for checking bearing preload.
- Locktite Blue
- Locktite Bearing Retaining Compound for Press-Fit Bearings
- Locktite Bearing Retaining Compound for Loose-Fit Bearings
- Non-Chlorinated Brake Cleaner or Methylhydite
- Prussian Blue
- Be sure to use bearing adhesive on bearing and races. Do not get it on the rollers or moving parts
- Be sure to use Locktite blue thread locking compound on all bolts and nuts
- Lift front of vehicle and place on jack stands
- Remove front drive shafts (both upper and lower ball joints will need to be disconnected – be careful not to damage wires and brake hoses)
- Front CV shafts are pressed/seized into hubs, need to press/hammer out (be careful not to damage front wheel bearings)
- Undo 3 differential support bots/nuts
- Remove Differential
- Be sure to clean all parts extremely well prior to assembly!
- Remove right side CV Shaft support tube bolts (2 of them – 16mm or 5/8” Head)
- Remove 4 carrier support bolts in cross pattern
- Remove Differential housing bolts (inverted torx)
- Remove Differential cover and support tube
- Remove carrier bearing shims and mark their location – do not mess up their location as this will cause the diff to fail after re-assembly if you put them in the wrong spot
- Break apart bearing roller cages and press the bearings off the carrier and press on the new bearings
- Remove pinion nut and press out pinion
- Remove Oil Seal (should come out by hand, be careful not to damage unless replacing)
- Break apart bearing cages and press out bearings from housing and off the pinion, noting location of any shims – VERY IMPORTANT
- Press new bearings into housing and onto pinion.
- Press pinion into housing and re-install seal.
- Tighten Pinion nut and check pre-load of pinion bearings. If bearings are too tight, remove crush collar, stretch and re-assemble until proper pre-load is achieved.
- Re-install carrier into housing with new bearing races and old shims and check contact pattern with Prussian Blue or other differential dye.
- If all is good, re-install support tube and hand tighten the bolts, re-install cover and tighten carrier bearing bolts in 3-4 steps. I tightened mine to abt 25ft/lbs on first step, then tightened the carrier bolts to 80-90ft/lbs in four steps, and then re-torqued the tube bolts to 80-90 ft/lbs in additional 3 steps.
- Tighten the cover bolts to abt 25-30ft/lbs (be careful not to stip the threads).
- You’re done!
Cause of Failure:
In my personal professional opinion the cause of pre-mature failure is due to three reasons:
- The carrier bearings (which were damaged the worst) are a Light-to-Medium Duty Bearing – thus the pre-fix on the part number – LM/KLM
- Poor lubrication passage design in the housing
- Not enough oil in the diff (I put about 1.5L of oil into my diff when it was full at 0.9L) – You don’t want to grossly overfill the diff, but the extra pint will go a long way to keep those bearings lubricated, especially in cold climates).
Original OEM Set: http://www.ebay.com/itm/2006-12-Mercedes-ML-W164-Front-Diff-Bearings-Hard-To-Find-Not-Sold-in-USA-/121224489131?hash=item1c398ae8ab&vxp=mtr
Hope this helps someone out there.
Cheers!
Last edited by NewMLGuy; 01-19-2014 at 12:19 AM. Reason: Additional info
11-29-2013, 10:02 AM
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Bearing Quality, Origin, Cause of Failure
I’ve had a long running thread on another forum and we’ve run into a big long discussion regarding quality of bearings and where they’re made. This is very informative, so I think it’s a ‘must read’ before you make a decision on what parts to use to rebuild your differential with.
A retired bearing failure analysis engineer had joined in on the discussion and offered his professional opinion on quality, origin, and possible cause of failure. Here’s what he wrote:
That being said, I don’t think there’s anything wrong with these ‘copied’ bearings themselves. I sell them as well, as a less expensive alternative to the real thing. Although I do believe that selling a copy and passing it off as the real thing is wrong and unethical.
A retired bearing failure analysis engineer had joined in on the discussion and offered his professional opinion on quality, origin, and possible cause of failure. Here’s what he wrote:
“I have been an engineer in the bearing industry since 1971, although now retired. My specialty was failure analysis, applications and quality control.
I know that some of the major companies including but not limited to Timken, seem to indoctrinate some of their younger staff into believing they are the only"good" manufacturer in the world. So you have to be careful of some of the comments made.
One of the Ebay ads showed some NTN brand bearings. No these are not Timken. But they are one of the four top Japanese brands, and equal to the best bearings made in the world. Anyone who tries to deny that is showing ignorance. I would be happy to use them in any vehicle of mine.
Both the pinion bearings come with the prefix "HM" whilst the side carrier bearings come with "KLM".
The"HM" prefix (Heavy-Medium) indicates a bearing of thick proportions,where the outside is much larger diameter than the bore, or shaft size. This allows for a steep taper angle, hence a high thrust capacity, as required for the pinion.
The"LM" prefix (Light-Medium) indicates a bearing of thin proportions,which has a finer taper angle more suitable to a higher radial load. These proportions allow for the use of smaller diameter rollers, so many more rollers can be fitted, giving the bearing a very high capacity.
So the LM sizes may have a higher capacity than the HM sizes!
The"K" prefix is used by SKF and *** to denote a bearing made to Timken specification, i.e: an imperial sized bearing. All other SKF/*** tapered roller bearings are ISO metric sized, usually 5 numerals starting with "3".
All other European manufacturers have copied this system.
Timken have never used this "K" prefix in any of their own factories,especially in the USA. However as an expansion program, they have bought out several factories to expand their range. These include Torrington-Fafnir (USA)encompassing IRB in Spain. They also bought out a factory in Poland.
Both the IRB and Polish bearings use the "K" prefix. And they now come in the traditional orange and black packets.
We have noticed a higher than normal failure rate with bearings from these plants, but I would expect Timken have put a lot of effort into improving the product. Note: I would not be prepared to say these Polish bearings are the cause of the Mercedes diff problem.
Timken USA does notmake size LM503311. It is a minor but essential variation of the LM503310. Only Timken Poland claims to make this size.
Other pictures show the bearing etching with "USA" and the "KLM"prefix. These marks do not appear in the one picture, and they should notappear on the same bearing. If they are on the same bearing, then I wouldexpect they are a Chinese or similar forgery.
Now in summation:
The poor service life that seems to appear in Mercedes front diffs, is probably totally unrelated to the selection of the bearings. To determine the cause of failure I would need to inspect the failed bearings, and possibly the complete diff.
It could be that they use the same gear set for front and rear which reverses the load as the front diff points the opposite way to rear. This has been normal practise until recently with other makers, but rarely shows a problem when they use part-time 4WD.
And over-filling the diff with oil is also a no-no! It would cause frothing of the oil leading to overheating, poor lubrication and possible seal leaks.”
So, what this means is that any Timken bearings bearing the prefix “KLM” can onlycome from Poland. What this also means is that 503311 Timken bearing race can only have the full part number of KLM503311 and can only come from Poland. Any bearings that are claimed to be Original USA Made are most likely a copy of the original being passed off as the real thing.I know that some of the major companies including but not limited to Timken, seem to indoctrinate some of their younger staff into believing they are the only"good" manufacturer in the world. So you have to be careful of some of the comments made.
One of the Ebay ads showed some NTN brand bearings. No these are not Timken. But they are one of the four top Japanese brands, and equal to the best bearings made in the world. Anyone who tries to deny that is showing ignorance. I would be happy to use them in any vehicle of mine.
Both the pinion bearings come with the prefix "HM" whilst the side carrier bearings come with "KLM".
The"HM" prefix (Heavy-Medium) indicates a bearing of thick proportions,where the outside is much larger diameter than the bore, or shaft size. This allows for a steep taper angle, hence a high thrust capacity, as required for the pinion.
The"LM" prefix (Light-Medium) indicates a bearing of thin proportions,which has a finer taper angle more suitable to a higher radial load. These proportions allow for the use of smaller diameter rollers, so many more rollers can be fitted, giving the bearing a very high capacity.
So the LM sizes may have a higher capacity than the HM sizes!
The"K" prefix is used by SKF and *** to denote a bearing made to Timken specification, i.e: an imperial sized bearing. All other SKF/*** tapered roller bearings are ISO metric sized, usually 5 numerals starting with "3".
All other European manufacturers have copied this system.
Timken have never used this "K" prefix in any of their own factories,especially in the USA. However as an expansion program, they have bought out several factories to expand their range. These include Torrington-Fafnir (USA)encompassing IRB in Spain. They also bought out a factory in Poland.
Both the IRB and Polish bearings use the "K" prefix. And they now come in the traditional orange and black packets.
We have noticed a higher than normal failure rate with bearings from these plants, but I would expect Timken have put a lot of effort into improving the product. Note: I would not be prepared to say these Polish bearings are the cause of the Mercedes diff problem.
Timken USA does notmake size LM503311. It is a minor but essential variation of the LM503310. Only Timken Poland claims to make this size.
Other pictures show the bearing etching with "USA" and the "KLM"prefix. These marks do not appear in the one picture, and they should notappear on the same bearing. If they are on the same bearing, then I wouldexpect they are a Chinese or similar forgery.
Now in summation:
The poor service life that seems to appear in Mercedes front diffs, is probably totally unrelated to the selection of the bearings. To determine the cause of failure I would need to inspect the failed bearings, and possibly the complete diff.
It could be that they use the same gear set for front and rear which reverses the load as the front diff points the opposite way to rear. This has been normal practise until recently with other makers, but rarely shows a problem when they use part-time 4WD.
And over-filling the diff with oil is also a no-no! It would cause frothing of the oil leading to overheating, poor lubrication and possible seal leaks.”
That being said, I don’t think there’s anything wrong with these ‘copied’ bearings themselves. I sell them as well, as a less expensive alternative to the real thing. Although I do believe that selling a copy and passing it off as the real thing is wrong and unethical.
Last edited by NewMLGuy; 11-29-2013 at 10:43 AM. Reason: Typo
01-04-2014, 06:32 PM
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FAKE BEARINGS !!!
Ladies and Gentlemen,
Unfortunately there is a dishonest person on this forum who sells bearings to unsuspecting, trusting people on eBay. I must warn you about this person and provide everyone here with proof to back my words!
So here it goes:
His handle on MBWorld.org is lasicm. On eBay his user name is also lasicm. He was recently banned from Benzworld.org where his handle was mostar1. He was banned for harassing members, including filling my thread with garbage rants about how his USA Timken bearings are real and mine are fake. Since he was banned from Benzworld, he has taken the fight here, where he continues badmouthing me. He has gone as far as stealing the procedure I wrote and published on Benzworld almost a year ago and posted it here telling everyone that he wrote it and that I’m the copy-cat. He has copied it with spelling errors and all!! [BTW Dan, that’s not how you spell Methyl Hydite!] His real name is Dan and he is from Houston, TX.
He found a bearings supplier in China who manufactures these hard to find bearings for him and sells them on eBay as the real thing. He used to tell everyone that the bearings he sells are Made in USA (see a photo below of his old eBay listing). Now he tells everyone that they are made in France, which is a lie. TheseKLM503349/11 bearings are only made in Poland.
You should never mix and match bearing sets! Furthermore, from the information I have, the KLM503349 cannot be bought separate from the KLM503311. So where this guy is getting them separately, I don't know. China? For sure! There is a good chance that these bearings will fail due to the fact that they are assembled from odds and ends that came from different factories. Stay safe and buy the OEM ones.
His KLM503311 race (or bearing cup) looks to be the only authentic Polish made Timken, but the bearing cone he is putting in with it is 150% a replica.
Please see the picture below which explains how to tell areal bearing from a fake.
I sell the genuine Timken Poland Bearings in a set I put together along with Genuine USA Made NTN bearings. You can find this set here: http://www.ebay.ca/itm/2006-12-Mercedes-ML-W164-Front-Differential-Bearings-Hard-To-Find-Not-Sold-in-US-/121224489131?pt=Motors_Car_Truck_Parts_Accessories &hash=item1c398ae8ab
The genuine bearings that are guaranteed to last at least as long as the original ones (so approx 100,000miles) if assembled correctly, meanwhile Dan is charging $320 for a set of bearings made in China! Which one wouldyou put in your vehicle? I think we allknow the answer.
If you are looking for instructions, specs, torque specs,etc., I've written and posted a procedure on how to rebuild a differential onthe W164, X164, and W251. You can find the procedure here: https://mbworld.org/forums/m-class-w164/522199-2006-2012-w164-successful-front-differential-rebuild.html#post5859305
In that same thread, I’ve posted an excerpt from a post published by a retired bearing failure analysis engineer on another forum. There you can find more evidence on how to tell a real bearing from a fake and that Lacism’s bearings are fake.
Due to forum rules, I’m not allowed to post links to other forums, but if you need more info, just look up my threads on here as well as Benzworld.
As for lasicm’s claim that he wrote the procedure - again, just go to the other forum and look at the date of when it was first published by me – February 22, 2013. I have thesame handle there, if anyone is interested.
Cheers to everyone and I hope that my rebuild procedure helps someone out there as well as this article helps steer someone clear of Lasicm’s bearings, because they will fail.
I am a licensed and certified mechanic. I wrote and published the procedure after rebuilding my own ML500’s front diff with almost the same cheap bearings I sell on eBay. It’s been good now for almost a year, so if anyone has any questions, feel free to PM me and I will be glad to help.
Good luck to all and god bless.
Unfortunately there is a dishonest person on this forum who sells bearings to unsuspecting, trusting people on eBay. I must warn you about this person and provide everyone here with proof to back my words!
So here it goes:
His handle on MBWorld.org is lasicm. On eBay his user name is also lasicm. He was recently banned from Benzworld.org where his handle was mostar1. He was banned for harassing members, including filling my thread with garbage rants about how his USA Timken bearings are real and mine are fake. Since he was banned from Benzworld, he has taken the fight here, where he continues badmouthing me. He has gone as far as stealing the procedure I wrote and published on Benzworld almost a year ago and posted it here telling everyone that he wrote it and that I’m the copy-cat. He has copied it with spelling errors and all!! [BTW Dan, that’s not how you spell Methyl Hydite!] His real name is Dan and he is from Houston, TX.
He found a bearings supplier in China who manufactures these hard to find bearings for him and sells them on eBay as the real thing. He used to tell everyone that the bearings he sells are Made in USA (see a photo below of his old eBay listing). Now he tells everyone that they are made in France, which is a lie. TheseKLM503349/11 bearings are only made in Poland.
You should never mix and match bearing sets! Furthermore, from the information I have, the KLM503349 cannot be bought separate from the KLM503311. So where this guy is getting them separately, I don't know. China? For sure! There is a good chance that these bearings will fail due to the fact that they are assembled from odds and ends that came from different factories. Stay safe and buy the OEM ones.
His KLM503311 race (or bearing cup) looks to be the only authentic Polish made Timken, but the bearing cone he is putting in with it is 150% a replica.
Please see the picture below which explains how to tell areal bearing from a fake.
I sell the genuine Timken Poland Bearings in a set I put together along with Genuine USA Made NTN bearings. You can find this set here: http://www.ebay.ca/itm/2006-12-Mercedes-ML-W164-Front-Differential-Bearings-Hard-To-Find-Not-Sold-in-US-/121224489131?pt=Motors_Car_Truck_Parts_Accessories &hash=item1c398ae8ab
The genuine bearings that are guaranteed to last at least as long as the original ones (so approx 100,000miles) if assembled correctly, meanwhile Dan is charging $320 for a set of bearings made in China! Which one wouldyou put in your vehicle? I think we allknow the answer.
If you are looking for instructions, specs, torque specs,etc., I've written and posted a procedure on how to rebuild a differential onthe W164, X164, and W251. You can find the procedure here: https://mbworld.org/forums/m-class-w164/522199-2006-2012-w164-successful-front-differential-rebuild.html#post5859305
In that same thread, I’ve posted an excerpt from a post published by a retired bearing failure analysis engineer on another forum. There you can find more evidence on how to tell a real bearing from a fake and that Lacism’s bearings are fake.
Due to forum rules, I’m not allowed to post links to other forums, but if you need more info, just look up my threads on here as well as Benzworld.
As for lasicm’s claim that he wrote the procedure - again, just go to the other forum and look at the date of when it was first published by me – February 22, 2013. I have thesame handle there, if anyone is interested.
Cheers to everyone and I hope that my rebuild procedure helps someone out there as well as this article helps steer someone clear of Lasicm’s bearings, because they will fail.
I am a licensed and certified mechanic. I wrote and published the procedure after rebuilding my own ML500’s front diff with almost the same cheap bearings I sell on eBay. It’s been good now for almost a year, so if anyone has any questions, feel free to PM me and I will be glad to help.
Good luck to all and god bless.
Last edited by NewMLGuy; 01-19-2014 at 12:20 AM.
01-09-2014, 03:38 PM
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COUNTERFEIT BEARINGS SEIZED AT TORONTO AIRPORT
A little more on this subject. I just got this little bit of news and wanted to share with everyone. This article was just brought to my attention:
COUNTERFEIT BEARINGS SEIZED AT TORONTO AIRPORT
as well as this little bit of new here:
http://www.stopfakebearings.com
So as a result, I've pulled my eBay listings containing the cheaper aftermarket bearings. And I will be looking to source these from another manufactuer. I'll let everyone know if and when they become available.
The original Timken and NTN bearings are always available at the link above.
COUNTERFEIT BEARINGS SEIZED AT TORONTO AIRPORT
as well as this little bit of new here:
http://www.stopfakebearings.com
So as a result, I've pulled my eBay listings containing the cheaper aftermarket bearings. And I will be looking to source these from another manufactuer. I'll let everyone know if and when they become available.
The original Timken and NTN bearings are always available at the link above.
01-17-2014, 10:43 PM
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2009 S550 AMG sport pckg. 2014 Ford F-150 Lariat Supercrewcab
Can I just say you are awesome????????? lol Afew questions. What is the pinion and carrier preload??? Any other specs would be useful. If it ever happens to mine I'd like to be ready to tell the dealer to go F%&k themselves lmao 
I've put a new 4.10 in my 07 mustang so I have the tools and know how
I've put a new 4.10 in my 07 mustang so I have the tools and know how
01-18-2014, 08:18 AM
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Preload
Can I just say you are awesome????????? lol Afew questions. What is the pinion and carrier preload??? Any other specs would be useful. If it ever happens to mine I'd like to be ready to tell the dealer to go F%&k themselves lmao
I've put a new 4.10 in my 07 mustang so I have the tools and know how
I've put a new 4.10 in my 07 mustang so I have the tools and know how
The pinion preload should be about 18 inch/lbs. Back-lash abt 0.009". This is the way I did mine.
Cheers.
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07-31-2014, 09:11 PM
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Mercedes c230
http://www.ebay.com/itm/MERCEDES-W164-ML-R-W251-FRONT-DIFFERENTIAL-4-BEARINGS-COMPLETE-KIT-WITH-503311-/181149228503?pt=Motors_Car_Truck_Parts_Accessories&hash=item2a2d55ddd7&vxp=mtr
08-05-2014, 05:52 PM
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ML350
Get it for less....
http://www.ebay.com/itm/MERCEDES-W164-ML-R-GL-FRONT-DIFFERENTIAL-REBUILD-KIT-NOT-SOLD-IN-US-KLM503311-/321468833042?pt=Motors_Car_Truck_Parts_Accessories&hash=item4ad9091d12&vxp=mtr
http://www.ebay.com/itm/MERCEDES-W164-ML-R-GL-FRONT-DIFFERENTIAL-REBUILD-KIT-NOT-SOLD-IN-US-KLM503311-/321468833042?pt=Motors_Car_Truck_Parts_Accessories&hash=item4ad9091d12&vxp=mtr
10-28-2014, 12:49 AM
#10
MBWorld Fanatic!
I thought it was worth pointing out that after much discussion, and having numerous posts of NewMLGuy deleted over on benzworld for being absolute nonsense, it has been determined that in fact, Timken bearings do have the country of origin stamped on them, such as USA, or Poland and all this chatter about the bearings NOT having the country stamped on them, or that they are fake is completely false. And that the combination of the USA bearing and Polish race is perfectly OK according to Timken.
FYI.
FYI.
02-12-2015, 10:06 PM
#12
Gentlemen!
I have successfully rebuilt my 2006 ML500 front differential and would like to share my experience with you!
I am a licensed/certified mechanic with experience in rebuilding diffs. I must say that doing this job is easy and any qualified/experienced mechanic should be able to handle it with ease. It would be a difficult task for a DIY’er, but not impossible.
Tools required:
Cause of Failure:
In my personal professional opinion the cause of pre-mature failure is due to three reasons:
Original OEM Set: Original OEM Timken KLM503349/KLM503311 Bearing Set Made in Poland
Hope this helps someone out there.
Cheers!
I have successfully rebuilt my 2006 ML500 front differential and would like to share my experience with you!
I am a licensed/certified mechanic with experience in rebuilding diffs. I must say that doing this job is easy and any qualified/experienced mechanic should be able to handle it with ease. It would be a difficult task for a DIY’er, but not impossible.
Tools required:
- 36mm impact socket for spindle nuts <li itxtHarvested="0" itxtNodeId="33">32mm impact socket for diff pinion nut
- Torx bit for front drive shaft bolt
- Assorted wrenches and socets
- 12 ton shop press
- Oxy-Acetylene torch (or other adequate heat source)
- Air hammer
- Compressor and Impact Wrench
- Torque Wrench - Click type ft/lbs and analog needle type for checking bearing preload.
- Locktite Blue
- Locktite Bearing Retaining Compound for Press-Fit Bearings
- Locktite Bearing Retaining Compound for Loose-Fit Bearings
- Non-Chlorinated Brake Cleaner or Methylhydite
- Prussian Blue
- Be sure to use bearing adhesive on bearing and races. Do not get it on the rollers or moving parts
- Be sure to use Locktite blue thread locking compound on all bolts and nuts
- Lift front of vehicle and place on jack stands
- Remove front drive shafts (both upper and lower ball joints will need to be disconnected – be careful not to damage wires and brake hoses)
- Front CV shafts are pressed/seized into hubs, need to press/hammer out (be careful not to damage front wheel bearings)
- Undo 3 differential support bots/nuts
- Remove Differential
- Be sure to clean all parts extremely well prior to assembly!
- Remove right side CV Shaft support tube bolts (2 of them – 16mm or 5/8” Head)
- Remove 4 carrier support bolts in cross pattern
- Remove Differential housing bolts (inverted torx)
- Remove Differential cover and support tube
- Remove carrier bearing shims and mark their location – do not mess up their location as this will cause the diff to fail after re-assembly if you put them in the wrong spot
- Break apart bearing roller cages and press the bearings off the carrier and press on the new bearings
- Remove pinion nut and press out pinion
- Remove Oil Seal (should come out by hand, be careful not to damage unless replacing)
- Break apart bearing cages and press out bearings from housing and off the pinion, noting location of any shims – VERY IMPORTANT
- Press new bearings into housing and onto pinion.
- Press pinion into housing and re-install seal.
- Tighten Pinion nut and check pre-load of pinion bearings. If bearings are too tight, remove crush collar, stretch and re-assemble until proper pre-load is achieved.
- Re-install carrier into housing with new bearing races and old shims and check contact pattern with Prussian Blue or other differential dye.
- If all is good, re-install support tube and hand tighten the bolts, re-install cover and tighten carrier bearing bolts in 3-4 steps. I tightened mine to abt 25ft/lbs on first step, then tightened the carrier bolts to 80-90ft/lbs in four steps, and then re-torqued the tube bolts to 80-90 ft/lbs in additional 3 steps.
- Tighten the cover bolts to abt 25-30ft/lbs (be careful not to stip the threads).
- You’re done!
Cause of Failure:
In my personal professional opinion the cause of pre-mature failure is due to three reasons:
- The carrier bearings (which were damaged the worst) are a Light-to-Medium Duty Bearing – thus the pre-fix on the part number – LM/KLM
- Poor lubrication passage design in the housing
- Not enough oil in the diff (I put about 1.5L of oil into my diff when it was full at 0.9L) – You don’t want to grossly overfill the diff, but the extra pint will go a long way to keep those bearings lubricated, especially in cold climates).
Original OEM Set: Original OEM Timken KLM503349/KLM503311 Bearing Set Made in Poland
Hope this helps someone out there.
Cheers!
02-13-2015, 07:39 PM
#13
MBWorld Fanatic!
A wheel bearing could possibly cause a simliar sound but would be localized to the wheel causing the noise.
The issue as has been discussed many time is a failed carrier bearing,
which thankfully can be replaced without mortgaging your house.
If it turns out you need replacement bearings, you can check here.
http://www.ebay.com/itm/MERCEDES-ML350-ML550-R350-GL500-GL550-FRONT-DIFFERENTIAL-US-BEARINGS-KLM503311-/221606853753?pt=Motors_Car_Truck_Parts_Accessories&hash=item3398cc3c79&vxp=mtr
03-09-2015, 02:12 PM
#14
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2006 MB R350
Diagnosis
2006 R350 W251 --
I was having an error with the ECS/ABS system that would not allow the car to drive forward as normal. With the vehicle in gear, the car would move forward, but as soon as I pressed on the accelerator, the abs system would kick in and bring the car to a standstill. I replaced an ABS sensor and the problem seemed somewhat less dramatic, so I replaced all the ABS sensors. While I had the car suspended on jackstands, I put it in gear and noticed that the front left tire starts out at somewhat the same speed as the other wheels, but would slowly come to a standstill while the other wheels continued to spin... So now I am wondering where the system is binding. I am thinking that it might be a carrier assembly bearing or maybe the axle from that wheel. Is there a way to tell before taking things apart just from 'symptoms?' It seems lke this is going to be costly or fairly time involved. (I'm only a driveway mechanic on occasion.) This -- along with the intake manifold flaps working improperly makes me want to drop this car and get a new one, but I still owe WAY too much (and other life events at the moment) to make that anywhere near reasonable right now...
I was having an error with the ECS/ABS system that would not allow the car to drive forward as normal. With the vehicle in gear, the car would move forward, but as soon as I pressed on the accelerator, the abs system would kick in and bring the car to a standstill. I replaced an ABS sensor and the problem seemed somewhat less dramatic, so I replaced all the ABS sensors. While I had the car suspended on jackstands, I put it in gear and noticed that the front left tire starts out at somewhat the same speed as the other wheels, but would slowly come to a standstill while the other wheels continued to spin... So now I am wondering where the system is binding. I am thinking that it might be a carrier assembly bearing or maybe the axle from that wheel. Is there a way to tell before taking things apart just from 'symptoms?' It seems lke this is going to be costly or fairly time involved. (I'm only a driveway mechanic on occasion.) This -- along with the intake manifold flaps working improperly makes me want to drop this car and get a new one, but I still owe WAY too much (and other life events at the moment) to make that anywhere near reasonable right now...
05-27-2016, 12:34 AM
#16
unnecessary but successful rebuild also
After much testing including isolating both front wheels I became convinced that my carrier bearings were bad and took it all apart only to find perfectly excellent bearings after 115k miles. I had already ordered the bearings, some from Lasicm, mercbenzspecialist, 1200 positive Ebay transactions and some from benzexpert on Ebay, 300+ positive transactions. Both served me very well. The job was very straight forward and a good advanced DIY project if you have a 20 tone press which you can probably buy at Harbor Freight very reasonably. As it turned out the noise coming from my front end was a failed front wheel bearing which is pretty straight forward too again requiring a 20 ton press.
06-08-2016, 03:25 AM
#17
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ML 320 W164
1xsculler, so the noise was not the diff bearings after all?
For someone like me that has "bearing-sounding noise" from the front at around 58MPH, how would you pinpoint the source between the diff and the wheel bearings?
For someone like me that has "bearing-sounding noise" from the front at around 58MPH, how would you pinpoint the source between the diff and the wheel bearings?
06-08-2016, 12:24 PM
#18
I am a pretty good DIYer, have done a fair amount of work on my cars over the years and I tried really hard to pinpoint the front end noise on my 2007 GL450. First I jacked one side of the front up just enough to get that tire off the ground. I started it up, put it in gear, listened carefully and it made the noise. Then I did the same on the other side and, again, it made the noise. Then I jacked the entire front end up with both front tires off the ground, E-brake on, rear wheels blocked, started it up and put it in gear. With heavy gloves on I carefully stopped each front wheel and listened. It made the noise with either tire stopped. Those experiments along with reading all of the posts about bad diff bearings on this forum had me leaning towards a diagnosis of bad diff bearings. So, I ordered the bearings and prepared to get into it. I kept checking for a bad wheel bearing at each stage of disassembly but not until I had the diff out, apart and saw that the carrier bearings were in excellent condition did I check the wheel bearings much more carefully and noticed that the left front bearing felt slightly rough when I rotated the brake rotor and the right one was silky smooth.
How would I avoid this mistake again? I'd remove the wheels, calipers and rotors and rotate each hub feeling for any roughness at all. Both hubs should rotate with a silky smooth feel.
A better mechanic than me might have been able to pinpoint the noise by driving the car and maybe I could have also if I hadn't had diff bearings on my mind.
The noise got so bad I was afraid to drive the car to the dealership, or anywhere else, for fear of doing more damage to expensive front driveline parts.
Once I was committed to taking everything apart it turned out to be a pretty simple job but it did consume some time.
The first wheel bearing was ruined by my incorrect installation but I got the second one in correctly and now all is well except I have something wrong with my Airmatic suspension which is unrelated to this issue.
How would I avoid this mistake again? I'd remove the wheels, calipers and rotors and rotate each hub feeling for any roughness at all. Both hubs should rotate with a silky smooth feel.
A better mechanic than me might have been able to pinpoint the noise by driving the car and maybe I could have also if I hadn't had diff bearings on my mind.
The noise got so bad I was afraid to drive the car to the dealership, or anywhere else, for fear of doing more damage to expensive front driveline parts.
Once I was committed to taking everything apart it turned out to be a pretty simple job but it did consume some time.
The first wheel bearing was ruined by my incorrect installation but I got the second one in correctly and now all is well except I have something wrong with my Airmatic suspension which is unrelated to this issue.
06-09-2016, 10:03 AM
#20
Again, if I were you I would remove the wheels, calipers and rotors so you can turn just the hubs by hand and feel for any roughness whatsoever. Even having the drive shafts still in the hubs had some dampening effect on detecting my slight bearing roughness. Only when I had the entire front end apart and saw that the carrier bearings were not the cause of the noise did I go back to very careful inspection of both wheel bearings and like I said, one was silky smooth and the other only very slightly rough.
A better mechanic than myself could probably have diagnosed the problem in the first place but I am not sure how.
06-13-2016, 08:42 AM
#21
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ML 320 W164
1xsculler, thanks for the advice.
When it stops raining (sometime after August) I'll get under it and investigate.
In the mean time, the new tyres (Goodyear Wrangler) mask any bearing noise, so I can pretend it's not there..
And no, I wouldn't recommend them..
When it stops raining (sometime after August) I'll get under it and investigate.
In the mean time, the new tyres (Goodyear Wrangler) mask any bearing noise, so I can pretend it's not there..
And no, I wouldn't recommend them..
06-20-2016, 02:25 PM
#22
MBWorld Fanatic!
115K miles on the original carrier bearings without damage must be a record.
In reading through the factory maint. sheet I didn't see an interval for replacing the oil in the front diff, or the transfer case.
1xsculler, did you ever replace the oil in your front diff?
Failures start as early as 30K's.
Mine was at around 60K.
BTW- You can purchase bearings directly at benzexpert.com, definitely genuine with the holographic seals on the boxes.
In reading through the factory maint. sheet I didn't see an interval for replacing the oil in the front diff, or the transfer case.
1xsculler, did you ever replace the oil in your front diff?
Failures start as early as 30K's.
Mine was at around 60K.
BTW- You can purchase bearings directly at benzexpert.com, definitely genuine with the holographic seals on the boxes.
Last edited by C230 Sport Coup; 06-20-2016 at 02:28 PM.
06-20-2016, 02:50 PM
#23
front diff. bearings
I got the car with 100k on it so its diff. oil change frequency I don't have. All I can say is that the diff. carrier bearings looked very good at 115k. I replaced them anyway as I had already ordered and received a set from the guy on Ebay with about 1200 positive feedbacks. They were the correct bearings with the hologram, etc. so far as I could tell. I heated the inner race moderately so I could pound them on fairly easily with a large socket applied to the inner race. I didn't sleep well that night fearing I may have damaged the inner race so I ordered another set from the guy on Ebay who has about 300 positive feedbacks. These looked to be correct too and this set I pressed on so all is well.
The pinion shaft bearings were silky smooth and there was no evidence of excessive wear in the oil so I left them alone.
My huge tires are ever so slightly more noisy than the stock tires on my wife's 2006 ML350 but by replacing the left front wheel bearing (twice too but that's another story I have posted somewhere on one of the forums) my front end is quiet.
The pinion shaft bearings were silky smooth and there was no evidence of excessive wear in the oil so I left them alone.
My huge tires are ever so slightly more noisy than the stock tires on my wife's 2006 ML350 but by replacing the left front wheel bearing (twice too but that's another story I have posted somewhere on one of the forums) my front end is quiet.
06-21-2016, 03:53 PM
#24
MBWorld Fanatic!
Do you happen to have the generic part number for the front wheel bearing?
I got the car with 100k on it so its diff. oil change frequency I don't have. All I can say is that the diff. carrier bearings looked very good at 115k. I replaced them anyway as I had already ordered and received a set from the guy on Ebay with about 1200 positive feedbacks. They were the correct bearings with the hologram, etc. so far as I could tell. I heated the inner race moderately so I could pound them on fairly easily with a large socket applied to the inner race. I didn't sleep well that night fearing I may have damaged the inner race so I ordered another set from the guy on Ebay who has about 300 positive feedbacks. These looked to be correct too and this set I pressed on so all is well.
The pinion shaft bearings were silky smooth and there was no evidence of excessive wear in the oil so I left them alone.
My huge tires are ever so slightly more noisy than the stock tires on my wife's 2006 ML350 but by replacing the left front wheel bearing (twice too but that's another story I have posted somewhere on one of the forums) my front end is quiet.
The pinion shaft bearings were silky smooth and there was no evidence of excessive wear in the oil so I left them alone.
My huge tires are ever so slightly more noisy than the stock tires on my wife's 2006 ML350 but by replacing the left front wheel bearing (twice too but that's another story I have posted somewhere on one of the forums) my front end is quiet.
06-21-2016, 05:52 PM
#25
Front wheel bearing 2007 GL450
I am sorry I don't. The first one I bought at O'Reillys for $99 with a three year warranty and the second from Mercedes for $175. If you called O'Reillys I am sure they would give you the part number. It had the speed sensor encoder in it. You could also find the same bearing on Ebay or Amazon.
