OM651 Engine. DEF usage
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E250 Diesel
OM651 Engine. DEF usage
How much DEF do you go through every 10k miles? I understand the tank capacity is something like 6 gallons. Do you feel you go through all of it? Mine is only about 3 gallons every 10k miles, which is my oil change interval.
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From: Ohio/Florida
'10 C300, '15 ML250BT, '22 M850i Vert
I wish I could be more specific, but mine with 60k has used very little. I drive about 10k a year, and the last time I filled the tank it over flowed with a 2 1/2 gal container. In other words that’s about what it takes a year.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
I realize this is an older thread, but I found it while trying to figure out if my DEF consumption was reasonable. (I guess It is...) My plan was to run it down until the warning appeared, then add 2-1/2 gallons and wait for the warning to reoccur. I've had the car now for a little more than 11,000 miles and I'm still waiting for the first warning... Since the car was on a dealer's lot before I got it, I'm assuming it was filled then.
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From: V E G A S
1922 Ford Model T / no OBD
My record shows 1 gallon of DEF per 65 gallons of fuel. This is short-period record, so can't say how accurate. Suppose after AEM bluetecs use more DEF than before, but I have no records to compare.
I drive my Sprinter with Scangauge all the time. The DEF warning light comes at 30% of tank, what should be good for another 2-3000 miles.
IMHO MB screw the DEF tank design on sedans, where they made big tank, to last between service, but deleted spare wheel.
Now I have to carry spare in the trunk, when refilling DEF is easy at almost each gas station, Walmart, Costco and more.
I drive my Sprinter with Scangauge all the time. The DEF warning light comes at 30% of tank, what should be good for another 2-3000 miles.
IMHO MB screw the DEF tank design on sedans, where they made big tank, to last between service, but deleted spare wheel.
Now I have to carry spare in the trunk, when refilling DEF is easy at almost each gas station, Walmart, Costco and more.
Last edited by kajtek1; Jan 12, 2023 at 07:58 PM.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
Well, I should be getting the warning any day now. I've used about 380 gallons of fuel which works out to about 5.8 gallons of DEF, and 70% of my 7.3 gallon tank is about 5.1 gallons.
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From: V E G A S
1922 Ford Model T / no OBD
Understand that 30% happen on Sprinter, who has reservoir lasting for 5-7000 miles. Easy to refill by station distributor since it is under the hood.
Sedans do have reservoir design to last for at least 13,000 miles between FSS calling for service, so logically the % should be different.
Than seeing what programmers did on some MB features, I could never figure out what they smoke, meaning the logics don't apply here.
I don't drive my sedan often, so might take me over 2 years to gain that experience.
Sedans do have reservoir design to last for at least 13,000 miles between FSS calling for service, so logically the % should be different.
Than seeing what programmers did on some MB features, I could never figure out what they smoke, meaning the logics don't apply here.
I don't drive my sedan often, so might take me over 2 years to gain that experience.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
Reviving an old thread...
After 12,000 miles I finally got the warning, in February of 2023. I added 2.5 gallons and waited for the warning to recur. In November of 2023, after 4000 more miles, I added another 2.5 gallons, not wanting to go into the winter with low level in the tank as I had heard the tank heater could cause problems if the level was low.
In July of 2024 I got a Scangauge. It told me the level was 20% (and no warning.) In the end of October, 2024, 5000 miles later, it still said 20%. With winter approaching, I added another 2.5 gallons. The car was parked on a slope, nose high. The level after adding showed 98%! It has since settled at 94%.
Scangauge told me the resolution of the reading was very coarse, but when I filled it it first said 98%, later 94%, and now 96% (over the course of a few miles), but, it had shown 20% for 5000 miles. (I think I'll have to recheck the programming for that gauge.)
Bottom line, I still have no idea how much DEF it uses, but it looks like it's less than 2.5 gallons for 4000 miles, and I'm still waiting for the warning to recur. In the summer...
How do you fill the thing without overflowing? The hose screws onto the tank, and there's no way to tell it's full until the hose fills up, and then there's no way to disconnect the hose without spilling the contents.
Oh, and I changed phones a while back and haven't been able to get the Autel to work since.
After 12,000 miles I finally got the warning, in February of 2023. I added 2.5 gallons and waited for the warning to recur. In November of 2023, after 4000 more miles, I added another 2.5 gallons, not wanting to go into the winter with low level in the tank as I had heard the tank heater could cause problems if the level was low.
In July of 2024 I got a Scangauge. It told me the level was 20% (and no warning.) In the end of October, 2024, 5000 miles later, it still said 20%. With winter approaching, I added another 2.5 gallons. The car was parked on a slope, nose high. The level after adding showed 98%! It has since settled at 94%.
Scangauge told me the resolution of the reading was very coarse, but when I filled it it first said 98%, later 94%, and now 96% (over the course of a few miles), but, it had shown 20% for 5000 miles. (I think I'll have to recheck the programming for that gauge.)
Bottom line, I still have no idea how much DEF it uses, but it looks like it's less than 2.5 gallons for 4000 miles, and I'm still waiting for the warning to recur. In the summer...
How do you fill the thing without overflowing? The hose screws onto the tank, and there's no way to tell it's full until the hose fills up, and then there's no way to disconnect the hose without spilling the contents.
Oh, and I changed phones a while back and haven't been able to get the Autel to work since.
Last edited by John CC; Nov 7, 2024 at 09:43 PM.
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From: WA State, USA
2014 Cummins, 2014 E250 Bluetec
My e250 om651 just has a cap on the top of the tank so go fill but it will overflow if ya mess it up. I usually wait till the light comes on and add a 2.5g, It last for a long time but I have not tried to mileage it.
FYI the tank level indicators (not displayed on MB for some reason) are horribly inaccurate. They do not track well so a scanner that checks them will not indicate accurately over time. My truck (when it had DEF) had the same issue although it has a gage. When I filled it up it would come down to about 3/4 then sit there for a long time then drop to 1/2 then hang out for a while then go to a 1/4 but would sit there for a long time also. On average my truck got 1000m/g DEF usage. Towing it would suck it down. Its a 6.7l cummins so much larger than the 2.0l.
My car gets about 40mpg average, truck gets about 19mpg average so guessing my car uses about 2000m/g DEF.
FYI the tank level indicators (not displayed on MB for some reason) are horribly inaccurate. They do not track well so a scanner that checks them will not indicate accurately over time. My truck (when it had DEF) had the same issue although it has a gage. When I filled it up it would come down to about 3/4 then sit there for a long time then drop to 1/2 then hang out for a while then go to a 1/4 but would sit there for a long time also. On average my truck got 1000m/g DEF usage. Towing it would suck it down. Its a 6.7l cummins so much larger than the 2.0l.
My car gets about 40mpg average, truck gets about 19mpg average so guessing my car uses about 2000m/g DEF.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
I wonder if you could just "stick" the tank? Anyone know if it's a straight line from the fill port to the bottom?
I don't see 40 mpg often, but then the GLK is not very aerodynamic, and I rarely get on the highway for more than a couple of miles.
I don't see 40 mpg often, but then the GLK is not very aerodynamic, and I rarely get on the highway for more than a couple of miles.
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From: WA State, USA
2014 Cummins, 2014 E250 Bluetec
I would have to investigate see if thats possible.
I have the same commute atleast 5 days a week, 53 miles one way. Morning is "usually" exactly the same unless there is a accident or someone jumps, coming home is a crap shoot and usually atleast halfway bad. Joys of traffic.
I have the same commute atleast 5 days a week, 53 miles one way. Morning is "usually" exactly the same unless there is a accident or someone jumps, coming home is a crap shoot and usually atleast halfway bad. Joys of traffic.
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E250 GLE300d
Wait until the warning light comes on, then add a 2.5 gallon box.
Don't think about it again for months.
I put roughly the same effort as washer fluid. I have 300K miles on two of OM651 powered Mercedes.
/
Don't think about it again for months.
I put roughly the same effort as washer fluid. I have 300K miles on two of OM651 powered Mercedes.
/
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
That is essentially what I have been doing, except I don't want it at or near the warning level when the heater comes on, so I've added 2.5 gallons in late fall and the warning has never come on since the first time.
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E250 GLE300d
/
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From: V E G A S
1922 Ford Model T / no OBD
Heater issue is known on Sprinters, who have sealed DEF reservoir and stupid heater failure cost > $3000 in reservoir replacement.
I don't drive sedan much lately, but AEM on Sprinters raised warning light to 30%, what should be plenty.
Bare in mind, MB has installed "dummy" gauge on DEF tanks. The signal from the sensor is send to computer module, who tells (on the scanner) the propaganda, not the real level.
ScanGauge will read the DEF level, but that doesn't mean it is actual level.
I had situation on Sprinter, where I topped-off the reservoir, what fooled the ultrasonic gauge.
The module, having no signal from the gauge, would calculate deduction from last read, who was about 35%.
So having full DEF, the gauge was showing 35%, going down. That lasted for 120 miles, when finally DEF level dropped down and exposed air gap, needed for gauge to work again and it did show 100% at the time.
I believe, that would I top off the reservoir having less than 20%, the module could go to 0 and famous count down would begin.
No clue if sedan has similar design, but good news the DEF heater on sedan is replaceable part, meaning cheap to replace.
I don't drive sedan much lately, but AEM on Sprinters raised warning light to 30%, what should be plenty.
Bare in mind, MB has installed "dummy" gauge on DEF tanks. The signal from the sensor is send to computer module, who tells (on the scanner) the propaganda, not the real level.
ScanGauge will read the DEF level, but that doesn't mean it is actual level.
I had situation on Sprinter, where I topped-off the reservoir, what fooled the ultrasonic gauge.
The module, having no signal from the gauge, would calculate deduction from last read, who was about 35%.
So having full DEF, the gauge was showing 35%, going down. That lasted for 120 miles, when finally DEF level dropped down and exposed air gap, needed for gauge to work again and it did show 100% at the time.
I believe, that would I top off the reservoir having less than 20%, the module could go to 0 and famous count down would begin.
No clue if sedan has similar design, but good news the DEF heater on sedan is replaceable part, meaning cheap to replace.
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E250 GLE300d
Then I cut the bottom off of it - which is the top once you turn it upside down and screw it in. It is now your "funnel".
Then buy a 2.5 gallon box of diesel fluid. You do need to push down on the "funnel" for the fluid to enter the car.
I normally pour the first few bottles carefully. After that I just pour continuously and push down continuously. There is some splash back. I use a paper towel on top of the bottle to prevent that.
Re-use the Mercedes bottle you cut. That stays in the car.
Good luck.
https://www.fcpeuro.com/products/vw-...ABEgJnZfD_BwE/
/
Last edited by mfab; Nov 26, 2024 at 07:32 AM.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
The one from Wal*Mart contains as much as 5 of those bottles and cost less than one. I'm part Scottish and won't be buying one of them any time soon!
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From: V E G A S
1922 Ford Model T / no OBD
Filling DEF with jug, can top it off, fooling the gauge.
The design vary between MY, but Sprinters do have relatively small DEF reservoir, who require more frequent fills. Additionally the gauge is dummy gauge, having computer module, calculating the level, when the gauge is not working.
So it happen on my Sprinter, that when I topped off DEF at 30% level, the gauge could not read the level for next 120 miles.
In the mean time, the module was substracting the usage from last readout, so having full tank, my gauge was slowly dropping down below 10%.
Then finally the DEF level dropped to create air gap and the gauge jumped to 100%.
I can only calculate, that would I top off DEF, having less than 20%, the calculated value could drop to 0 and famous countdown would start. ...
Last edited by kajtek1; Nov 27, 2024 at 02:57 PM.
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From: WA State, USA
2014 Cummins, 2014 E250 Bluetec
Guess if ya top it off all the way. Regardless not sure how 20% would be only 120miles? In my case not concerned as I do 110 miles a day commute so would only have couple of starts before it reads assuming it uses what ya said it does. I guess the sprinters would use different percentage of DEF, the car om651 20% would be like 2000miles in my car.
Regardless these DEF gages are horribly inaccurate no matter which diesel ya have, if ya even have a gage which my car doesnt. I actually just got the message yesterday so gonna throw in a jug and worry about it in about 5000 miles.
Regardless these DEF gages are horribly inaccurate no matter which diesel ya have, if ya even have a gage which my car doesnt. I actually just got the message yesterday so gonna throw in a jug and worry about it in about 5000 miles.
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From: V E G A S
1922 Ford Model T / no OBD
E class Bluetec were build with DEF tank to last between the service. One of those ideas, that doesn't work in real life.
The tank deleted spare wheel, so when I don't care about making 20,000 miles on DEF fill, I would rather have spare wheel in the car.
If you use jugs, adding 2.5 gallons when warning light comes seems to be the safest way to do.
I prefer filling DEF at Truck Stops and my GLE is having convenient DEF fill next to diesel fill.
E is not recommending using pumps and since I don't drive it much, the tank of DEF would reach 3 years, before I would need to refill it, so I am refilling the jugs at truck stop and dump smaller amounts to E.
As I mentioned above, the DEF gauge is dummy gauge and the module is cheating on drivers.
On my recently purchased Lad Rover, the DEF has real gauge. When I drive downhill, the ScanGauge will show for example 60%, when going uphill, it will show 55% and it will bounce when I cross a curb.
The tank deleted spare wheel, so when I don't care about making 20,000 miles on DEF fill, I would rather have spare wheel in the car.
If you use jugs, adding 2.5 gallons when warning light comes seems to be the safest way to do.
I prefer filling DEF at Truck Stops and my GLE is having convenient DEF fill next to diesel fill.
E is not recommending using pumps and since I don't drive it much, the tank of DEF would reach 3 years, before I would need to refill it, so I am refilling the jugs at truck stop and dump smaller amounts to E.
As I mentioned above, the DEF gauge is dummy gauge and the module is cheating on drivers.
On my recently purchased Lad Rover, the DEF has real gauge. When I drive downhill, the ScanGauge will show for example 60%, when going uphill, it will show 55% and it will bounce when I cross a curb.
Last edited by kajtek1; Nov 29, 2024 at 10:13 AM.
