DEF for Sprinter?

[<<B-Guy>>]

Will some kind soul give me a quick education of DEF ?

I have owned a Duramax diesel but it was a 2008, I think the last year before DEF was required, so know nothing about it - other than what the acronym stands for!

Now we have a sprinter van camper on order!

Two questions ....

(1) Is it important (for warranty or other reasons) to use a Mercedes product which I am guessing is more costly(!) or s DEF pretty much a generic product I can buy at Wally World and save $$?


(1) I have read a few posts about computer glitches with MB software when it comes to adding DEF and suggestions that these glitches "Might" be avoided if you top up regularly rather than waiting for an "Add DEF" warning. I guess I should do that rather than tempt fate - but how often would be "regularly?"

every thousand miles reasonalble?


(3) Any other info I should be aware of about DEF to get off on the right foot and hopefully avoid problems appreciated!


Thanks ......... Brian.

[avanti]

Originally Posted by Wingeezer

Will some kind soul give me a quick education of DEF ?

I have owned a Duramax diesel but it was a 2008, I think the last year before DEF was required, so know nothing about it - other than what the acronym stands for!

Now we have a sprinter van camper on order!

Two questions ....

(1) Is it important (for warranty or other reasons) to use a Mercedes product which I am guessing is more costly(!) or s DEF pretty much a generic product I can buy at Wally World and save $$?

No. All DEF is the same, assuming it comes from a sealed container. It does (theoretically) have a shelf life, but it is measured in years. Not going to be a problem at Walmart. Just check the seals.

Entering "broken record" mode: It is in any event illegal in the US to tie warranty coverage to OEM parts or supplies.

(1) I have read a few posts about computer glitches with MB software when it comes to adding DEF and suggestions that these glitches "Might" be avoided if you top up regularly rather than waiting for an "Add DEF" warning. I guess I should do that rather than tempt fate - but how often would be "regularly?"

every thousand miles reasonalble?

That would be more than reasonable. I usually try to guess when it will take a 2.5 gallon box. Others do it more often. There are ways to program a Scan Gauge II to show DEF level (assuming your Sprinter doesn't already have this feature--some do). I haven't tried it yet, but intend to. There is a fringe theory around that keeping the tank fully-topped-up at all times keeps some kind of internal sensors wet and therefore protected. I know of zero evidence to support this theory. I put this in the same category as needlessly-frequent oil changes.

(3) Any other info I should be aware of about DEF to get off on the right foot and hopefully avoid problems appreciated!

Really, the only things you can do are (a) drive lots of highway miles, and (b) be very careful not to introduce contaminants when you add DEF.

Actually, highway miles have little to do with DEF per se. It is actually the diesel particulate filter (DPF) that is most at risk by too much stop-and-go driving and/or long idling. Folks tend to lump all aspects of the emissions systems (along with a few other troublesome sensors, such as the wheel speed sensors) into one category, and it is easy to slip into referring to the whole thing as "DEF".

[<<B-Guy>>]

Originally Posted by avanti

No. All DEF is the same, assuming it comes from a sealed container. It does (theoretically) have a shelf life, but it is measured in years. Not going to be a problem at Walmart. Just check the seals.

Entering "broken record" mode: It is in any event illegal in the US to tie warranty coverage to OEM parts or supplies.

That would be more than reasonable. I usually try to guess when it will take a 2.5 gallon box. Others do it more often. There are ways to program a Scan Gauge II to show DEF level (assuming your Sprinter doesn't already have this feature--some do). I haven't tried it yet, but intend to. There is a fringe theory around that keeping the tank fully-topped-up at all times keeps some kind of internal sensors wet and therefore protected. I know of zero evidence to support this theory. I put this in the same category as needlessly-frequent oil changes.

Really, the only things you can do are (a) drive lots of highway miles, and (b) be very careful not to introduce contaminants when you add DEF.

Actually, highway miles have little to do with DEF per se. It is actually the diesel particulate filter (DPF) that is most at risk by too much stop-and-go driving and/or long idling. Folks tend to lump all aspects of the emissions systems (along with a few other troublesome sensors, such as the wheel speed sensors) into one category, and it is easy to slip into referring to the whole thing as "DEF".

Many thanks Avanti, just the kind of info I needed!

I resisted asking if I could just "Pee" in the tank - I read that DEF was urea and water!

"Pee" was apparently used as a dye fixative in Scotland years ago in the making of Harris Tweed from what I have read, and I believe more recently by the Confederates in the Civil War, as a source of potassium nitrate for gunpowder, so who knows! <useless info mode off.>

Brian.

[Knit]

The 2012 Sprinter Operators Manual says:

“The exhaust gas aftertreatment requires a reducing agent, Diesel Exhaust Fluid (DEF), in order to function correctly. Filling up the DEF tank is usually part of the service scope. DEF consumption depends on operational and driving conditions; the supply does not have to suffice until the next scheduled service. For this reason, refill the DEF tank regularly during vehicle operation, or, at the latest, after the first warning message has been received from the on-board computer.”

- so MB says it’s ok to keep it topped off like you would with windshield wiper fluid or wait until you get the FIRST warning light. Given how easy it is to buy and add DEF, it doesn’t make sense to wait until the second warning. This isn’t like changing oil sooner than recommended. It’s just keeping the tank full enough.

“Depending on the vehicle version, the DEF consumption of: Cargo Van/Passenger Van is approximately 2322 MPG “

- this is a useful average number since most of us in the US think in terms of mpg. So I usually buy the cheaper 2.5 gallon packages and put one in about every 5000 miles. Once I filled at a truck stop from the pumps.

“Only use DEF in accordance with ISO 22241. The exhaust gas aftertreatment may otherwise be damaged.”

- the commonly available DEF fluids like Peak and those from branded by auto parts stores like Napa all say they meet this MB specification. Most truck stops like Love’s have it in pumped form even cheaper.

[avanti]

Originally Posted by Knit

- so MB says it’s ok to keep it topped off like you would with windshield wiper fluid or wait until you get the FIRST warning light. Given how easy it is to buy and add DEF, it doesn’t make sense to wait until the second warning. This isn’t like changing oil sooner than recommended. It’s just keeping the tank full enough.

I completely agree with this. I would NEVER recommend waiting for the second warning. That is just asking for trouble. The recommendation is to not even wait for the first warning (which, as you say, is not at all difficult).

My "changing oil" comment was directed toward a small number of people who fill their DEF tanks at every few fuel stops, which I consider a waste of effort. Even then, you are also right that this is merely pointless, not wasteful in the sense that too-frequent oil changes are.

Sorry if I was unclear.

[Knit]

Avanti - I got what you were saying the first time. And I agree that changing the oil when not necessary is inefficient both in terms of cost and to the environment. People post complaints about what service cost yet go on to explain that they change their oil twice or even more times than needed. Some of them even after testing the oil that shows it has plenty of life left.

[Rok]

O.K. I have a couple of questions/comments for this thread.

(1) When my warning light comes on, I think the unit is 1.6 gallons low--not enough for a full 2.5 gallon box. it sounds like others can wait until it will take 5 gallons (!) ? Am I missing something here?

(2) Everyone says it is not a problem to add the stuff, but I can't seem to add DEF without spilling it and it is very very corrosive from what I've heard. So filling it comes with a routine of spraying everything off with a hose, or if I'm on the road, dumping at least a 1 gallon bottle of water to rinse it off. I must be missing something here, too, no?

On this last trip I used one of those DEF pumps at a truck stop and it shut off when the rig was full (yep, at 1.6 gallons). Only a couple of drips got on the rig and the was easy to take care of. I presume that is the same stuff? I was told it was, and others here seem to imply that it is.

Thanks in advance for any information.

[avanti]

Originally Posted by Rok

O.K. I have a couple of questions/comments for this thread.

(1) When my warning light comes on, I think the unit is 1.6 gallons low--not enough for a full 2.5 gallon box. it sounds like others can wait until it will take 5 gallons (!) ? Am I missing something here?

(2) Everyone says it is not a problem to add the stuff, but I can't seem to add DEF without spilling it and it is very very corrosive from what I've heard. So filling it comes with a routine of spraying everything off with a hose, or if I'm on the road, dumping at least a 1 gallon bottle of water to rinse it off. I must be missing something here, too, no?

On this last trip I used one of those DEF pumps at a truck stop and it shut off when the rig was full (yep, at 1.6 gallons). Only a couple of drips got on the rig and the was easy to take care of. I presume that is the same stuff? I was told it was, and others here seem to imply that it is.

Thanks in advance for any information.

Well, Sprinters come with four differently-sized DEF tanks:

3.2 gallon for OM642 (6 cyl)
4.7 gallon for OM651 (4 cyl)
4.9 gallon for OM642 (6 cyl)
5.8 gallon for cab chassis

The "add DEF" warning is supposed to come on when you have 1.5 gal left. So, it sounds like you have the 3.2 gal tank. I have the OM651 with the 4.7 gal tank, so I can easily wait until I am down 2.5 gal and still avoid the warning.

As for filling, there are all kinds of containers with different kinds of spouts and hoses. You should try different ones till you find one you like. Lots of folks swear by the official MB 1 gallon container as being particularly easy. Some people recommend buying one (relatively expensive, obviously) and refilling it from a larger container. I have never tried one, so I am just passing on advice.

[Roadtrek Adventuous RS1]

Originally Posted by avanti

No. All DEF is the same, assuming it comes from a sealed container. It does (theoretically) have a shelf life, but it is measured in years. Not going to be a problem at Walmart. Just check the seals.

Entering "broken record" mode: It is in any event illegal in the US to tie warranty coverage to OEM parts or supplies.

That would be more than reasonable. I usually try to guess when it will take a 2.5 gallon box. Others do it more often. There are ways to program a Scan Gauge II to show DEF level (assuming your Sprinter doesn't already have this feature--some do). I haven't tried it yet, but intend to. There is a fringe theory around that keeping the tank fully-topped-up at all times keeps some kind of internal sensors wet and therefore protected. I know of zero evidence to support this theory. I put this in the same category as needlessly-frequent oil changes.

Really, the only things you can do are (a) drive lots of highway miles, and (b) be very careful not to introduce contaminants when you add DEF.

Actually, highway miles have little to do with DEF per se. It is actually the diesel particulate filter (DPF) that is most at risk by too much stop-and-go driving and/or long idling. Folks tend to lump all aspects of the emissions systems (along with a few other troublesome sensors, such as the wheel speed sensors) into one category, and it is easy to slip into referring to the whole thing as "DEF".

YES..I'm very interested in who and and what cost for this...?
Who did the work .... Mercedes Benz dealership couldn't help...

Also, is this similar to See Level guages?? I'm thinking of having my old Roadtrek standard guage replaced??? They are just basically worthless... provide just an estimate...

Please tell me more about your experience with the Scan Gauge 2........

By the way.... you're absolutely correct about the different sizes of DEF fluid tanks...
I have the 4.9 gallon .....

I also had a defective emissions system that was "drinking" DEF fluid like nobody's business..... Mercedes Benz dealership replaced the entire emissions system at 39,000 miles...

I just came back from a 2,000 miles trip....used less than one half gallon of DEF fluid....
A Mercedes Benz expert told me that a properly working emissions system should go the complete distance between 10,000 miles service intervals.... just make me nervous as hell since I had experienced a failure before with the light coming on requiring a complete reset from the dealership..... which I had to pay for prior to the system getting replaced!!

I wasn't very happy about that...

Tell me about Scan Gauge 2....is it integrated into the dashboard or do you have a separate readout device??

[BBQ]

.

5 gallon is a BIG bucket

/

[rowiebowie]

Some of those who report trouble-free miles in their Sprinter vans swear by keeping the DEF tank topped out regularly. Not waiting for warning lights.

http://www.classbforum.com/forums/f5...html#post77886

[avanti]

Originally Posted by Roadtrek Adventuous RS1

Please tell me more about your experience with the Scan Gauge 2........

The Scan Gauge is a device that plugs into your OBD2 port, just like a diagnostic scanner, except that it is intended more as an "all the time" monitoring device, rather than a repair tool. It is able to monitor many different parameters reported by your engine's ECU. These include useful things like Percent Load, instantaneous MPG, coolant temperature, and many more. You can select four of them to display at once. It is easy to switch what is displayed. It is a little box that sits on your dash.



It can also display and often clear "check engine" codes, which is very useful for giving you a rough idea of what is going on. It is, however, no replacement for a full-blown scanning tool.

There is a (rather geeky) way to enter special programming sequences ("X-codes") to teach it vehicle-specific codes. One of them is apparently DEF level.

Almost all serious Sprinter geeks have a Scan Gauge or equivalent.

[Roadtrek Adventuous RS1]

Originally Posted by BBQ

.

5 gallon is a BIG bucket

/

Yes.. provided your emissions system is running perfectly..
Mine was defective... I didn't know that and within 3,500 miles the system ran low and caused a problem...

Mercedes Benz at first wouldn't own the problem and told me to just keep adding fluids.... 11,000 miles later the system crapped out.

[Belzar]

DEF is not complicated. My experience: DEF tank holds about 6 gallons and lasts 7000-10000 miles. Low DEF level light (not countdown warning) comes on when tank 1/4 full, so lots of miles to find some DEF. DEF is available all over in 1 gallon or 2.5 gallon jugs: gas stations, convenience stores, truck stops, Walmart, auto parts stores etc. Easiest is to fill up at truck lane at a truck stop that has a DEF pump. If you are really conservative, carry a gallon jug with you - not worth the space or weight to carry the big 2.5 gallon jugs. That's it. I don't really think about it until light comes on or if I'm prepping for a many-thousand-mile trip.

[Roadtrek Adventuous RS1]

Originally Posted by Belzar

DEF is not complicated. My experience: DEF tank holds about 6 gallons and lasts 7000-10000 miles. Low DEF level light (not countdown warning) comes on when tank 1/4 full, so lots of miles to find some DEF. DEF is available all over in 1 gallon or 2.5 gallon jugs: gas stations, convenience stores, truck stops, Walmart, auto parts stores etc. Easiest is to fill up at truck lane at a truck stop that has a DEF pump. If you are really conservative, carry a gallon jug with you - not worth the space or weight to carry the big 2.5 gallon jugs. That's it. I don't really think about it until light comes on or if I'm prepping for a many-thousand-mile trip.

You would think that it would be as easy as that.... like a low fuel light on the dash ....

My problem was that the DEF light came on and the Sprinter immediately went into the "countdown" for limited restarts......

That was BEFORE I had the replacement emissions system....

Now that the new system and updated software my Sprinter hardly used DEF fluid at all.....

Used about 3/4 or less of a half gallon.. in 2,000 miles......

Based on that...I figured it could go about 10,000 miles on the 4.9 gallon tank....

[Abn1SG]

Originally Posted by Roadtrek Adventuous RS1

You would think that it would be as easy as that.... like a low fuel light on the dash ....

My problem was that the DEF light came on and the Sprinter immediately went into the "countdown" for limited restarts......

That was BEFORE I had the replacement emissions system....

Now that the new system and updated software my Sprinter hardly used DEF fluid at all.....

Used about 3/4 or less of a half gallon.. in 2,000 miles......

Based on that...I figured it could go about 10,000 miles on the 4.9 gallon tank....

I had the same problem too, twice, where the countdown started as soon as the first warning message appeared and both times to the dealership (1.5hrs away) for nox sensor replacement and software update each time. So from then on, I go approximately 2500 miles and top it off, usually around 1.5 gals at a diesel/DEF station, just to avoid it from happening again.

[Roadtrek Adventuous RS1]

Originally Posted by Abn1SG

I had the same problem too, twice, where the countdown started as soon as the first warning message appeared and both times to the dealership (1.5hrs away) for nox sensor replacement and software update each time. So from then on, I go approximately 2500 miles and top it off, usually around 1.5 gals at a diesel/DEF station, just to avoid it from happening again.

I hope they did this under warranty.. they replaced my entire emissions system including the Nox sensors, catalytic converter and whatevgeer else. Would have cost over $4,000 … thankfully, I didn't have to pay for all that.


Now, it doesn't use that much. I would continue to press Mercedes to fix your problem.


Do you have a DEF gauge on the dashboard... I do NOT..
Like you driving more than 2,000 miles makes me nervous, but ,this last 2,000 miles the usage was less than 1/2 gallon

[Abn1SG]

Originally Posted by Roadtrek Adventuous RS1

I hope they did this under warranty.. they replaced my entire emissions system including the Nox sensors, catalytic converter and whatevgeer else. Would have cost over $4,000 … thankfully, I didn't have to pay for all that.


Now, it doesn't use that much. I would continue to press Mercedes to fix your problem.


Do you have a DEF gauge on the dashboard... I do NOT..
Like you driving more than 2,000 miles makes me nervous, but ,this last 2,000 miles the usage was less than 1/2 gallon

Yes, it was all done under the warranty and no, my unit doesn't have a DEF gauge, would have been extremely convenient if it did.

[Roadtrek Adventuous RS1]

Originally Posted by Abn1SG

Yes, it was all done under the warranty and no, my unit doesn't have a DEF gauge, would have been extremely convenient if it did.

What make model and year is your vehicle?????

[avanti]

Originally Posted by Abn1SG

no, my unit doesn't have a DEF gauge, would have been extremely convenient if it did.

Which is why the aforementioned ScanGauge X-code is interesting. I need to get around to trying it.