Anthony Deneke

I have a 2014 Ram 3500 Dually and my DEF gauge doesn't work the float in the tank sticks I've had it fixed once already under warranty and now it doesn't work again. Is this an issue that a lot of other people are having?

gsbrockman

The DEF tank does not use a float to determine the diesel exhaust fluid level.

Anthony Deneke

So it's electronic? What determines the DEF level?

gsbrockman

The DEF level is determined by various electronic sensors at varying heights within the tank. The presence of diesel exhaust fluid across the contacts of the sensors determines the fluid level.

Since DEF freezes at 12*F, they cannot use a standard float-style sending unit.

Lary Ellis (Top)

Just tossing out a thought here since I don't use DEF...Just wondering if there are different brands of DEF fluid and if changing brands might help?

Maybe one brand might be more conducive for that type of sensor.

Harvie

Chemist told me all DEF has to be exactly the same to pass the govt standards, just different packaging for different sellers.

Soooo different prices for the exact same thing....

Anthony Deneke

Well I will take it back to the dealer for warranty.

gsbrockman

Through 144,944 miles...I've been through 36 fillups, 223.2 gallons, and $670.86 of DEF. Of those 36 fillups, only 10 times have I purchased DEF in a 2.5 gallon container as I was not nearby a bulk retailer of DEF; all else has been purchased at Love's, Flying J, T/A, Pilot, etc.

In a nutshell....as stated above...due to the ISO ratings, DEF=DEF=DEF=DEF.

The gauge reading is not very linear (IMO) and I wonder if the OP has an actual problem.

I've never had my truck back for any emission related issues. I've found that if I run DEF low until this message comes on



or if I get down to the 200 mile to de-rate message



and then re-fill with bulk DEF, one keeps a "fresher" quality of DEF in their tank. Obviously----those that only drive 4,000 to 6,000 miles per year with no towing might be best to only add DEF a gallon at a time....IMO.

I have ran the DEF low enough to get this message a couple of times...

Anthony Deneke

Well I will have it fixed at the dealership then I will try and fill the def at a truck stops from now on. Like you said maybe it's better. Thanks for the tips.

johnh

sort of like rv tank sensors? i know they get dirty and need cleaning.....i think there is a sensor cleaning additive for the rv's .....maybe there is something for def tank sensors?

locopilot750

My def tank will read "Full" until the def level gets down to about 60%, then it starts to read normally as level drops.