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2020 Silverado 2500 DEF usage

gjohnston7
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cr2256 Enthusiast

cr2256

Posted
Posted

Quick comment, I took a drive earlier and it moved back up to 1/2 full.  The description above from @redwngr is likely what is happening.  Thanks again!

  • 1 month later...
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CO 2020 GMC AT4
CO 2020 GMC AT4

I'm experiencing the same issue, especially when pulling a good load.  Hauling hay in western CO, empty flatbed gooseneck weighing about 5k, then loaded with 14k of hay back up hill to the house.  7 t

gjohnston7
gjohnston7

Take it in to the dealer.  It is my understanding that they have two different software upgrades that help with the sensor.  It improved the accuracy for me but it is still a long way from perfect.   

hotairgypsy
hotairgypsy

Was at the dealership today for an error code and when i got my truck back they said there was a recall on the def system and they took care of it while I was there...They said it was something to do

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shadow gray 2020 hd Enthusiast

shadow gray 2020 hd

Posted
Posted

Have gone 800 some odd miles, added 2.5 gallons of def and the level shows to be very close to what it was when I drove the truck off the lot.  So probably around 320 miles per gallon.  

  • 3 weeks later...
Jeepvkng1 New Member

Jeepvkng1

Posted
Posted

Slightly different because I actually am on my second part being replaced in 10k miles. At 2k I noticed a burning smell and smoke under my hood. Took it in. They said it was a ceramic coating burning off. I accepted this. 5k miles later I take my trailer on a 3k mile trip. At the end of the trip engine light comes on. Its the PPF. Packed full of carbon.  Dealership said it was the smell and smoke from the issues at 2k. Had it replaced.  Blue def usage is tops at 300 miles a gallon. Its now in the shop because the blue def float sensor is bad and was false reading and putting the truck into limp mode. GM is repairing that without a code. From what I read people have been getting 1k miles a gallon out of this model. Mine is just one exhaust issue after another.

shadow gray 2020 hd Enthusiast

shadow gray 2020 hd

Posted
Posted
13 hours ago, Jeepvkng1 said:

Its now in the shop because the blue def float sensor is bad and was false reading and putting the truck into limp mode

Kind of wondering if this is a common issue and this is something I am kind of watching for on mine right now.  My level showed it was at like 3 bars a couple weeks ago, according to the supplemental manual it should have been able to take 3.5 gallons of def.  I added less than 1.5 gallons and it was full at the tank, overfilled.  The level then showed one bar less than full.  Drove for about a hundred miles with it at that level and then the level went to full, all bars lit up green.  It has been showing full for the past 200+ miles since.  I question the accuracy of this.

Jeepvkng1 New Member

Jeepvkng1

Posted
Posted

When the sensor went it would go all over the place. Full, half full 160 miles down to none at all while in park. Took 2 trips to the dealership to get them to realize that it was reading full and there was one gallon of def in the tank. 

  • 1 month later...
Jason Cro New Member

Jason Cro

Posted
Posted

7500 miles so far on my 2020, picked it up with a full def tank and I’ve put over ten gallons in it myself. Just made a 2k miles trip pulling a 24’ Livestock trailer Not even half loaded And went through 5 gallons easily. 

shadow gray 2020 hd Enthusiast

shadow gray 2020 hd

Posted
Posted

My gauge stayed pegged to the full side for nearly 1000 miles.  Finally went down one bar, then after about another 500 miles it went down another bar.  Will refill it when I get to about 3 bars and see how much it takes to fill it up.  So not really sure how it is doing now, but seems to be a little better than my early estimations.  

redwngr Senior Enthusiast

redwngr

Posted
Posted

Anyone interested in finding out what their truck is really getting for def mileage, find a nearby bulk def location.  Likely in a truck stop. Likely in the truck lanes. 

 

This 3.0L wasn't full when I got it so today I decided to fill it so at next fill I'll be able to calculate mpg. 

Anyway, with the new def fill beside the fuel fill it is super easy to use the bulk pumps.

 

The do have auto shut off.  I was in noisy fuel lanes so there was no way it would be possible to hear change in sound as fluid level starts up fill tube. 

DEF pump nozzle shut-off worked perfect.  No splash back. 

 

 

Just like checking fuel mileage, the only way to check def mileage is to fill tank, record odometer, drive, refill tank.

Miles driven divided by gallons to refill.....

 

If the tank isn't filled at both the start or end of exercise, then the mpg is just a wild ass guess.

Rguerra Enthusiast

Rguerra

Posted
Posted

I have a 2020 Duramax 3500 single axle 4x4 pickup and I have used over 10 gallons of DEF fluid since new.  I am currently at 4700 miles with 1/2 of the DEF tank remaining according to the DEF gauge.  This seems excessive to me since my brother has the same truck in 2018 that he has never added DEF fluid to in 14k miles.  He is at the 30% mark in his pickup but hes waiting to get that level really low before adding more since it has been in the truck so long.

Jeepvkng1 New Member

Jeepvkng1

Posted
Posted

My problem seems to have been fixed? since I had the def tank replaced.  They did it because I kept complaining about it and after a lot of screaming and several trips to the dealer after the gauges kept freaking out they said it was per customer request. Night and day difference all around.  Def usage is where it is supposed to be and gas mileage has improved.  Thinking they may have thrown in a update also but nothing was said to me. 

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  • 3 weeks later...
Drew510 New Member

Drew510

Posted
Posted

I also had a 2016 DRW Silverado and I just got a 2020.  I’m in Canada so we go by KM.  I’ve driven about 1700km and burned half a tank of DEF.  it seems very excessive to me.  I called the dealer and they are looking into it .  

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