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2020 GMC 2500 6.6 GASSER leveled with 35's MPG????

Gabe Bunn

By Gabe Bunn
in 6.6L Gas V8 (L8T)

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Gabe Bunn Enthusiast

Gabe Bunn

Posted
Posted (edited)

Just about to order a or buy a 2020 or 2021 crew GMC 2500 GASSER with the 6.6 4x4. Me and Ford diesels are parting ways after about 20 years. I have grown tired of FORD and these new emissions. What kind of MPG can I expect with a leveled 2020 GMC 2500 with 35's? Looking for averages in city/hwy and towing? Also, ANY pics with this configuration would be greatly appreciated. Leaning towards silver but pics can sway me.  Wanting a A/T aggressive tire. No M/T and no highway tire. THANKS for ALL the HELP and ADVICE.

Edited by Gabe Bunn
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i82much Enthusiast

i82much

Posted
Posted

i get about 12 winter and 13 summer in mixed driving with a 2016 2500HD crew gas 4x4 on bfg at KO2’s in the stock 245/75r17 size.  I would be shocked if you got better than 11 in mixed driving.  

gearheadesw Senior Enthusiast

gearheadesw

Posted
Posted (edited)

12 mpg in my gasser, skinny 35's, little level kit and shocks. Diesels get bette fuel milage, but still have emission problems, going into limp mode. Like all modern diesels..... And whoops, wrong forum, again, sorry.

Edited by gearheadesw
  • 4 weeks later...
  • 2 weeks later...
texasnavy05 Enthusiast

texasnavy05

Posted
Posted

I'd take every mpg report with a grain of salt. I logged my mileage in fuelly for dozens of tanks. Mpg was consistently less than the dic said. Most people report their better numbers from the dic and not the actual mileage. For reference I'm stock height ccsb 4x4 and I get 11-11.6 on nearly every tank.

 

Here's a previous thread on fuel efficiency

 

https://r.tapatalk.com/shareLink/topic?url=https://www.gm-trucks.com/forums/topic/228093-66-gas-mpg/&share_tid=228093&share_fid=33003&share_type=t&link_source=app

 

and you could expect a level and bigger tires to slightly affect it from there. My guess is you would get 10.5-11mpg

 

Sent from my SM-G892A using Tapatalk

 

 

 

 

  • Like 2
TrailBoss1 Enthusiast

TrailBoss1

Posted
Posted

I just traveled to a vacation home 190 each way (PA to  Delaware) with a brand new 3500 HD 6.6 gasser. It’s not “broken in and had 100 miles on odometer before the trip.  With judicious throttle I was surprised to get 16.6 MPG round trip on DIC; 15.5 hand calculated. Stock Trailrunner tires on 20” wheels.

Stand By Enthusiast

Stand By

Posted
Posted
On 10/29/2020 at 4:42 AM, Robert Setters said:

TOYO AT3's 12.5x35.  12MPG normal back and forth to work . 9.5-10MPG pulling my 22 foot boat.

new truck.jpg

What kind of speedometer and/or odometer differences are you noticing?

  • 2 months later...
L8T Enthusiast

L8T

Posted
Posted
On 10/29/2020 at 2:42 AM, Robert Setters said:

TOYO AT3's 12.5x35.  12MPG normal back and forth to work . 9.5-10MPG pulling my 22 foot boat.

new truck.jpg

OT but what size rim you running? And suspension mods?

  • 3 months later...

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