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Posted

Is it a thing that the DEF gage in the DIC will show full when it’s not? I took it to the dealership for warranty work and it was down one green square, pick it up the next day, and I’m sure they didn’t add any, full. I drove for about a week, and just did a 200+ mile trip towing our TT, still full..is it a thing that I need looked at? Or common issue. How many miles you guys getting out of your DEF tank?

Posted
2 hours ago, Thankful said:

About a thousand miles per gallon.

I'm getting no where near that but I do tow frequently.  I think that's probably right if just running the highway unloaded.

Posted

Definitely keeping a close eye on this on my truck.  Hoping it is just a matter of the system needing a few cycles as per the tech bulletin that redwngr posted in another thread, but I need to get the truck in to a dealer anyway for another issue.  

Posted
4 hours ago, CRApex said:

I'm getting no where near that but I do tow frequently.  I think that's probably right if just running the highway unloaded.

I've never towed.  So you're probably right. Towing will increase DEF usage.

Posted

I have the 2020 Silverado 2500 HD and just got back from a 3700 mile trip towing a ~7000lb travel trailer.  I had to fill my 4.5 gallon DEF tank three times so I am getting way less than 1000 miles per gallon!  It eats DEF like crazy. Mine starts giving me warnings that my DEF range is 975 miles about 150-200 miles after I fill it.   I took it to the dealer when we returned and they said they did a software update related to DEF but I haven't driven enough yet to see if it changed anything.

Posted (edited)

I'm getting about 500 miles per gallon of DEF towing an 8000 lb Airstream trailer. The DEF gauge works well and shows about the right amount of DEF over distance traveled.  It appears that the newer diesels; Ford, GM and Fiat Chrysler all use more than prior years to meet more stringent emission requirements. We're not alone.

Edited by unit
Posted

When the fuel usage is increased (like when towing) the def use will also increase, by about the same percentage.

 

 

Posted

Another thing with this truck...mine is never accurate. They did the update a few months back. I feel like I bought a beta tester vehicle.

Posted (edited)
6 hours ago, KC Desert said:

Another thing with this truck...mine is never accurate. They did the update a few months back. I feel like I bought a beta tester vehicle.

I agree, that's why I don't buy first year of a new generation. I'm looking to order a 2021 3500 AT4, barring anymore serious issues.

Edited by SilveradoX2
Posted
15 hours ago, SilveradoX2 said:

I agree, that's why I don't buy first year of a new generation. I'm looking to order a 2021 3500 AT4, barring anymore serious issues.

i had more issues with my 2017 than I had on my 1st 2020, put 40k on it and just traded it in.  The issue here is the def gauge, 2017 didn't even have one, mine has been pretty accurate though and even if its a bit off I really wouldn't call a serious issue.

Posted

From the GM techlink article:

 

Segmented DEF Level Gauge

The current 2020 Silverado 1500 and Sierra 1500 models have a DEF level gauge on the instrument cluster that provides drivers with a representation of how much DEF is in the DEF tank up. (Fig. 2) The DEF level gauge does not operate like a typical float-style gauge that is used in a fuel tank. The Engine Control Module (ECM) monitors the DEF level and consumption rate in order to calculate an estimated range. DEF levels are detected by the DEF level sensor.

 

There may be some fluctuation in the amount of DEF represented on the DEF level gauge. After filling the DEF tank, it may take a few key cycles to register the correct amount in the DEF tank. With the new segmented DEF level gauge, it is possible that after adding 5 gallons (18.9 L) of DEF that the gauge reads as a full tank after the fill event. However, if the actual level of DEF is just entering the last segment on the gauge, the gauge is likely to drop by one segment shortly after driving after the fill event. As a result, a driver could have an initial impression that the vehicle consumes an excessive amount of DEF.

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