DEF

[dunrovin1955]

I took delivery of a 2016 Ram 3500 on 11/20/15. I don't use it for daily driver. The DEF tank is 3/4 full. I have heard the DEF will go bad and if it does what will happen when I drive the truck. How long will the DEF stay good but if it goes bad what happens to the motor. Throw a code or just what? Thanks, Brent

[K0LCB]

I think it's safe for at least a year. Sister's truck sat for a year, she never had a problem

[1retired06]

Never a problem with my dually, and I also use occasionally plus towing. I get no readout on DEF life, but have never gotten any bad DEF. I wait til I get the half full warning (5 Gallons on Ford), which leaves me plenty of time to pick some up rather than carrying around.

[Bama Camper]

Well, all you have to do is camp more!!

When I originally bought my 2013 RAM, one of the service guys at the dealership suggested I only fill the DEF tank half full so I would never have old DEF. I did for a few months, but then realized I would be OK filling the tank because even though I don't use mine for a daily driver either, I expended the DEF rapidly enough so it would never really be old. When towing I get around 750 mpg of DEF. When my DEF gauge hits 1/4, I fill it. I figure the longest I've ever had any DEF in the tank is 6 months. I always buy mine in bulk at the truck stop instead of off the shelf. I'm guessing it's fresher that way - you never know how long it's been on the shelf or in a warehouse when it's in the container. It's a whole lot cheaper at the pump also. Last time I bought the price was 2.49/gal. as compared to $8 - $9/ gal in the container.

If it does get old, I wouldn't think it would hurt the engine. The DEF is burned in the SCR system which is after the engine anyway. Not sure how old DEF would affect that system.

[Beau2010]

Like BC, I also only fill the DEF tank at truck stops. Don't have to mess with one more container and spill it all over the side of the truck trying to fill. Just applied for a Flying J credit card so don't have to walk into the cashier's desk although we can't use the truck pumps in some states; anybody know why?

[CORattler]

Hopefully, this link will provide some answers to your questions regarding DEF...
http://govictoryblue.com/2013/10/08/...exhaust-fluid/

[TLightning]

I buy my DEF at Wally World. They have just come out with DEF in their own brand. Around $7 for 2 1/2 gallons, about $4 less than name brand.

[dunrovin1955]

Thanks for all the input guys. Makes me feel better about the DEF.

[washley1]

I'm just glad I still have my 08 that is pre DEF. It would only be one more thing I'd have to remember! I do have a 2014 BMW 328D, and it uses DEF, but I never have to think about it. The dealer does oil changes at 10000 mile increments, and they always check and refill the DEF. Interesting thing is after 10000 miles, the level indicator never flashes a low level warning. Little bitty thing must only use a thimble full per year!

[Artemus Gordon]

DEF is no big deal. I get 3500-4000 per tank of DEF. Tractor Supply has off brand that's pretty cheap. I not heard of DEF going bad unless it's allowed to much air. It gets crusty in the funnel.

[Jimmer]

Just a reminder for all with trucks with DEF make sure that you wash out your nozzle you use with water. You do not want those crystals going down inside your DEF tank it might damage your DEF pump. I have a 2015 Ford F350 Platinum with nice stainless chrome exhaust tip. It is amazing how clean they stay, no soot.

[pkbridges77]

quote:Originally posted by Artemus Gordon

DEF is no big deal. I get 3500-4000 per tank of DEF. Tractor Supply has off brand that's pretty cheap. I not heard of DEF going bad unless it's allowed to much air. It gets crusty in the funnel.

Agree! I guess it depends on your perspective, but I have zero complaints about DEF. I am so grateful to have been able to upgrade to the 6.7 for its sheer pulling power, and it runs quiet and clean. DW would have never wanted a stinky noisy diesel prior to the new emission equipment, and this is now her vehicle of choice!

[Rondo]

I called one of the companies that produce the DEF- the name of the company slips my mind at the present but it is one of the leading companies. I talked to one of the engineers for the company and asked him specifically if there is a shelf life on their product. He said that there is but it normally is a two year period and he also told me that if it freezes it shortens the life drastically. If it is in the tank of your TV it will be burned at a regular basis and normally a full tank of 5 gallons will last at least 4000-5000 miles. This also depends on if you are towing or not. I have run my tank down so the computer let me know I had 100 miles till the vehicle would go into the limp mode. I have a 2012 Chevy 3500 so it only gives me that signal instead of a regular gauge to show me the actual amount in the tank. Mine truck does not throw a code or anything!

[RKassl]

My 2016 GMC Sierra Denali has a nice new feature regarding the DEF tank. When you fill the DEF up the information center indicates "DEF OK." Then at about 1/2 to 3/4 through the tank of DEF it starts to reports the percentage left so that you have a pretty good handle of remaining fluid. In addition, and I haven't seen it yet the information center is supposed to tell me when I am going through a DPF filter regen-cycle.

[mhs4771]

Bob, that'sinteresting about the shelf life. I have always read that Heat is the killer on DEF and that freezing would effect it at all. So I wonder what's correct?

[08UltraRider]

I've seen several threads on different forums asking the same thing so I'd like to put this out there....

Can anyone give an example where the DIC gave the EXHAUST FLUID QUALITY POOR message and it was because the DEF's shelf life expired?

I'm not talking about the GM's NOX sensor issue in 2011 either.... where that was the message on the DIC and some dealers went as far to say "you didn't buy DEF from GM is the problem" That issue had nothing to do with the quality of the DEF but it was NOX sensors going bad in the first year they introduced SCR.

I just thought I'd throw that out there because IMHO... I don't feel it's something to be concerned about... Especially now as there are more and more SCR equipped diesel trucks out there every year.

Every source I've come across from different manufacturers are consistent in saying stored out of sunlight at room temperature the shelf life is about 2 years... Again... as there are more and more SCR equipped trucks out there I doubt you'll be able to find DEF that's anywhere close to being two years old.

IMO... I don't believe freezing/thawing has any effect on it either... Mine has been frozen/thawed many times over the last 3 winters with no issues.

From a document I have:

A 32.5% solution of DEF will begin to crystallize and freeze at 12 deg F (-11 deg C). At 32.5%, both the urea and water will freeze at the same rate, ensuring that as it thaws, the fluid does not become diluted, or over concentrated. The freezing and unthawing of DEF will not cause degradation of the product.


I'm not trying to downgrade the question by any means... It's a valid question.... I just thought I'd throw that out there to hopefully put some minds at ease!

[RKassl]

My dealer said that they had a customer that tried to fool the DEF and filled DEF tank with water. Got the bad DEF message. It is very simple to have a sensor in the tank that can differentiate between water and the specific gravity or electrical conductivity of the urea water mixture know as DEF.

[08UltraRider]

quote:Originally posted by RKassl

My dealer said that they had a customer that tried to fool the DEF and filled DEF tank with water. Got the bad DEF message. It is very simple to have a sensor in the tank that can differentiate between water and the specific gravity or electrical conductivity of the urea water mixture know as DEF.

Anything to save a buck.... Sometimes our trucks are smarter than the people who own them!

What happens is the NOX sensors will detect excessive NOX and then the system will adjust the amount of DEF injected. When that doesn't work the EXHAUST FLIUD QUALITY POOR will come on and if not corrected limp mode is next.

Tap water contains minerals and metals that could damage an expensive SCR system....

[WeBeFulltime]

quote:Originally posted by RKassl

My 2016 GMC Sierra Denali has a nice new feature regarding the DEF tank. When you fill the DEF up the information center indicates "DEF OK." Then at about 1/2 to 3/4 through the tank of DEF it starts to reports the percentage left so that you have a pretty good handle of remaining fluid. In addition, and I haven't seen it yet the information center is supposed to tell me when I am going through a DPF filter regen-cycle.

Nice feature but not so sure it's "new". My 2012 F350 is similar but instead of percentage left tells you how many miles left till empty. Yes, it does also flash message during region cycle.

[RKassl]

New to me!