Will diesel exhaust fluid goes bad?

[raptor]

friend told me to make sure that DEF fluid is fresh, but what happen if like me I don't use my motorhome that much. Would DEF in tank gone bad? I'm sorry if I'm repeating this question.

Thanks

[NO3putt]

DEF fluid if stored at normal temperature will last around a year or more. Google the brand you have and check specifications. Skip

[raptor]

My question is in MH tank? it's not what i put in. the one in our tank for years. my rig is 2016 forester. this is my first time to add def because it only have 6400 miles. as you can see i don't it that much for now.

[Teetime]

I would encourage you to search the forum for DEF and Julian Date, both will give you all you can read on the subject.

There seem to be so many variables about DEF Julian date, manufacture date, shelf life, and storage issues I'm not sure anyone can answer your question with accuracy.

I also have a vehicle which may go months before I take another road trip, and dread the day that I get some kind of a Bad DEF alert.

The next time I go in for service, I'm going to check into having a drain tap installed so I can just dump it and fill with new DEF fluid if needed.

[rlh1957]

Probably starts smoking like running out of DEF. But this is a great question for those that drive their home on wheels. I never thought about it because I have a truck and it doesn't go much over a year on a tank of DEF

[Mad Cow]

Also, with DEF sitting that long in RV, there could be a potential issue with DEF crystallizing in the system, especially the DEF filter and injector. Diligent maintenance of these systems is critical. I deal with diesels commercially, but have given up buying any of the new emissions laden nonsense out today. Even for my commercial uses, I have resorted to using factory reman pre-EGR diesels to avoid these hassles. Thing is, a Dutch company called Amminex developed a canister style of urea delivery in vehicles similar to a propane tank several years ago. 100% urea in a salt substrate. No liquid to pour, no shelf life concerns, no freezing issues, no end user hassles. And it is so effective that EGR could be eliminated and still meet EPA standards. Just change out the cartridge when needed just like changing out a propane tank. Cartridges are reusable and refilled at a facility.

Yet we have to live in the virtual Stone Age and deal with panther piss. So much of the world is light years ahead of us.

[larrytbm]

Yes, my tank holds over 5 gal and that would last me over one year. So I wait til I get the warning about low DEF and then only add 2.5 gal rather than completely filling the tank. You may want to only add 1 gal at a time.

[DieselDrax]

Originally Posted by rlh1957

Probably starts smoking like running out of DEF. But this is a great question for those that drive their home on wheels. I never thought about it because I have a truck and it doesn't go much over a year on a tank of DEF

DEF/SCR doesn't reduce smoking or particulates, that is what the DPF does. Running out/low on DPF doesn't make it smoke but it will trigger a speed-limited limp-mode if not corrected in time.

My truck has a DEF sensor and if there is a problem with the DEF or DEF flow then I will get a warning message about "poor DEF quality, see dealer" and then a countdown until max speed is reduced.

Q. What is the shelf life of DEF?
A. The shelf life of DEF is a function of ambient storage temperature. DEF will degrade over time depending on temperature and exposure to sun light. Expectations for shelf life as defined by ISO Spec 22241-3 are the minimum expectations for shelf life when stored at constant temperatures. If stored between 10 and 90 deg F, shelf life will easily be one year. If the maximum temperature does not exceed approximately 75 deg F for an extended period of time, the shelf life will be two years.

Q. How can I determine when the DEF I have purchased was
manufactured?
A. All DEF packages will have a date code located somewhere on the product. The date code will allow you determine the date the DEF was made. 1 gallon containers will have a laser code imprinted on the bottle. 2.5 and 5 gallon containers have a small date code label applied to the bottle. Drum and totes will have a label applied to either the top or side of the product.
The first digit of the date code represents the DEF batch number and the next 6 digits reflect the date that the batch was filled.

Hope this helps.

[FFred]

The DEF dries out , our method is to fill up to the top every 1,000 miles or so , usually 2 days driving.

And fill to the brim at home , or when not using the unit .

Even with this method we can get an exhaust check engine light after a long sit.

I ignore it now and in a day or so of driving it goes out.

[DreiHunde]

Here is PEAKs response to my "decipher the date code" request. Good to know info and it does mention how temp can reduce shelf life.

Hello,

Thank you for your email.

The product has a two year shelf life assuming it has been stored at 86 F or less. If it stored above 86 degrees, then it can be reduced down to six months.

Here is an example code that deciphers the batch code for diesel exhaust fluid.

Example Code |Method to Decipher
----------------------------+----------------------------------
PB160071555 |PB = LOCATION
|16 = Year + 1 (2015)
|007 = Days remaining in year
|(Reverse Julian Date) December
|25th
|1555 = Batch Code


The first two letters or numbers can change depending on blend facility but the codes all translate the same based off of ISO standards.

Regards,

Peak Tech Services

[Skyliner]

Be careful filling to the "brim" if you live in cold climates. DEF can freeze and damage to your DEF tank can occur if it freezes when overfilled.

The secret to DEF is to DRIVE your vehicle that uses it. What better excuse to go on more trips.

From what I understand, crystallization is a big concern. My truck's DEF system actually reverses pump flow at vehicle shutdown to clear the DEF fluid from the thin line that runs form the DEF tank to the injector.

[KatanaPilot]

It's not too difficult to extract (siphon) the DEF out of the tank. That's what I do annually since we don't use the MH enough.


A couple of gallons of DEF is cheap compared to the cost of MB emissions system repairs or a breakdown in the middle of Alaska.

[FFred]

"The product has a two year shelf life assuming it has been stored at 86 F or less. If it stored above 86 degrees, then it can be reduced down to six months."

As a snowbird perhaps this is the hassle .86F is common in FL in winter and NE in summer.

One thing I have noticed is if the RV is parked on pavement , its usually fine.

If parked on the lawn , where tires will sink in , a much higher throttle is required to move the first foot or so,and the chance of the light is much higher.

[raptor]

Well after reading a few sites including this one. Let say I didn't get answers but even more confused and scared of not knowing what I really have to do? The other site was saying something about modern diesel vehicle is so smart to siphon out fluid from line before shut down so it will not freezes and turned to crystal. To all the geniuses who designed the vehicles must have thought through all that what we're discussed here. They must have known about shell life of this fluid. I know in my profession as aircraft builder, we are asking a lot of "what if" or may be not the same down here.

It's my 2 cents

[dave-g]

So if I wanted to drain and start with a fresh tank of DEF- how does one dispose of the old DEF- checked several web sites- they say to contact local authorities but not to put in drain.

[Mikegjax]

Originally Posted by dave-g

So if I wanted to drain and start with a fresh tank of DEF- how does one dispose of the old DEF- checked several web sites- they say to contact local authorities but not to put in drain.

Spread it on your lawn. It is urea. Not harmful.

[dweaver2]

Consider the option of having the system removed from your vehicle. It is not necessary, only the gov and truck manufacturers push the system. Your power will increase as does your mileage. We improved avg of 8/mpg increase.

[DieselDrax]

Originally Posted by dweaver2

Consider the option of having the system removed from your vehicle. It is not necessary, only the gov and truck manufacturers push the system. Your power will increase as does your mileage. We improved avg of 8/mpg increase.

DEF/SCR doesn’t reduce fuel economy or power. Sounds like you are thinking of the DPF and the power increase as the result of installing a tune as the DPF doesn’t reduce power either.

8mpg increase is only believable if you spend most of your time doing short trips or city driving which results in frequent regens and then installed a tune and removed the emissions equipment but even then 8mpg is a stretch.

[timfromma]

I like the idea of having a drain valve installed in the DEF tank.

[MacGumbo]

Some warranties don't cover bad DEF and the repair can be expensive.

While at a Dodge dealership a person who had a quite new 1500 EcoDiesel was told that the DEF he put in his truck was old and below specs and therefore he had to eat the repair costs, over $4000. He was furious because he took every precaution to use fresh DEF. He was making quite a scene to the point that customers were videoing him while the whole staff was trying to calm him down.

He told them to eff off, saying he wasn't going to fix it and would drive it with the check engine light on. They told him that it would be impossible because after about 150 miles the vehicle would shut down automatically and there was nothing he could do to stop it except repair the problem.

He stormed out and I don't know what became of that.

I have the GC Ecodiesel and as soon as the warranty is up, the DEF system is outta here! I refuse to be held hostage by such a fickle, nonproductive, unproven system that can render my $60,000 vehicle useless because of piss.

I have already, in the first two years had the tank, injector, line and catalytic converter replaced due to this system, thank God they warrantied it.

Originally Posted by timfromma

I like the idea of having a drain valve installed in the DEF tank.

Low DEF in the tank is also very bad because it will accelerate crystallization in the tank and line to the injector.