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Posted
2024 3500 Denali in the driveway. Picked it up yesterday and drove home 340 miles. The 10 speed is crazy smooth. Mileage driving through the hills of Missouri and Arkansas saw a best of 19.1 and an average of 18.5. The overall ride really wasn't any different than my 21 2500. I will say the Digital Variable Steering Assist of the Denali feels more accurate than my 21 SLT.
 
Couple of things I have noted. The drive selector blocks the bottom left corner of the 13.4" screen. There is no longer variable volume stetting, or startup volume on the radio. GM has changed the tone of the turn indicator. The parking brake did not auto set when parking in my drive, same spot my 21 would auto set based on the grade.

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Posted

I have had 2 of the L8T gas engine 3500's. One with the 6 spd and one with the 10 spd. 

Hand calculated MPG is generally 15-16.5 at highway speeds (55-65) 

I have never seen anything approaching 18 no matter what the conditions. 

 

Posted
On 4/12/2024 at 12:23 PM, 64BAwagon said:

I have had 2 of the L8T gas engine 3500's. One with the 6 spd and one with the 10 spd. 

Hand calculated MPG is generally 15-16.5 at highway speeds (55-65) 

I have never seen anything approaching 18 no matter what the conditions. 

 

We took a trip to Utah last August in my 21 and over a 700+ mile stretch averaged 18.8 mpg 

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Posted
2 hours ago, 64BAwagon said:

Distance driven divided by gallons used is the only true accurate measure of MPG. 

Even then you get discrepancies. If a pump automatically clicks off but it’s close enough to full that it doesn’t draw any suspicion, it will seem as if you got better mileage than you did. 

Posted

have  done really well on the highway in 20, 22 and 23 gas 2500....16-21mpg

 

the city especially where I live is where I get smoked down to 9mpg

 

does not like stop and go......once moving its actually pretty good considering the size of the motor, weight and how big the trucks are

 

pulled up next to like a 2010 silverado 2500 other day and it looked like a Tacoma compared to mine

Posted (edited)
On 4/11/2024 at 6:17 PM, Grjfer said:
2024 3500 Denali in the driveway. Picked it up yesterday and drove home 340 miles. The 10 speed is crazy smooth. Mileage driving through the hills of Missouri and Arkansas saw a best of 19.1 and an average of 18.5. The overall ride really wasn't any different than my 21 2500. I will say the Digital Variable Steering Assist of the Denali feels more accurate than my 21 SLT.
 
Couple of things I have noted. The drive selector blocks the bottom left corner of the 13.4" screen. There is no longer variable volume stetting, or startup volume on the radio. GM has changed the tone of the turn indicator. The parking brake did not auto set when parking in my drive, same spot my 21 would auto set based on the grade.

PXL_20240411_232358771.jpg

PXL_20240411_220610670.jpg

pretty rare find right there....dont see mny Denali gas versions or 3500s for that matter

 

nice truck man, really a beautiful ride!..... I liked the wheels of previous model though....

 

coming from an LT to high country the digital steering was very noticeble for me, much easier for slow speed maneuvering, I dont know why its not standard across all trims aside from $$$

Edited by Dunn
  • Like 1
Posted (edited)

I have filled my tank a couple dozen times since I got my scangage. I have a monitor on the number of gallons in the fuel tank that tells me how much fuel I have left. Its is much more accurate than the gauge in the dash. I have run it down to the low fuel light before filling. When I fill I always do it with the lever on the slowest setting and then do not add after the auto stop. The scangage will always show exactly 36.1 gals after filling. I am not seeing any inconsistency in the amount. 

I also have an instant mpg and an mpg for the current key cycle. When comparing the data to whats on the dashboard mpg monitor, the numbers on the scangage are different and are a closer match to what I find when I calculate miles vs gallons. They are more accurate than the dash but they still vary from the actual miles vs gallons measurement. 

 

BTW, the GMC speedo and tach are so much nicer than the Chevrolet on the 24's. 

Another place where a serious truck person should have designed them rather than the art history soy boy that GM let create this abomination. 

 

 

Edited by 64BAwagon
  • Like 1
Posted (edited)

That's a great looking  truck Grjfer !

Edited by BCGM
Posted
On 4/15/2024 at 8:29 AM, 64BAwagon said:

I have filled my tank a couple dozen times since I got my scangage. I have a monitor on the number of gallons in the fuel tank that tells me how much fuel I have left. Its is much more accurate than the gauge in the dash. I have run it down to the low fuel light before filling. When I fill I always do it with the lever on the slowest setting and then do not add after the auto stop. The scangage will always show exactly 36.1 gals after filling. I am not seeing any inconsistency in the amount. 

I also have an instant mpg and an mpg for the current key cycle. When comparing the data to whats on the dashboard mpg monitor, the numbers on the scangage are different and are a closer match to what I find when I calculate miles vs gallons. They are more accurate than the dash but they still vary from the actual miles vs gallons measurement. 

 

BTW, the GMC speedo and tach are so much nicer than the Chevrolet on the 24's. 

Another place where a serious truck person should have designed them rather than the art history soy boy that GM let create this abomination. 

 

 

Interesting.

I too have a Scan Gauge III and find it closely resembles the dash readout. They should be getting the same info????

Still, what I found on my 2018 was the dash info was much more accurate when towing than when untowed. We’re heading on a flat trip to Alabama next week and I’ll have my first comparison with all three. Scan gauge, dash and old school computing. Should be “interesting”.

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