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Posted

Is anyone running larger than stock tires on a new 6.6 gas 2500 or 3500?  Interested in learning about what kind of hit your mpg took if so, and would love to hear any feedback on your setup.  

Posted

Larger then stock is a wide range
Big mudders....big highway tires....35s.... 40s

Anytime u put bigger heavier tires on ur gonna take a hit 1 or 2 mpg
But can't say yet on my 2020 as I haven't bought the big tires yet

There is a few thread with tire size and mpg.... just search mpg u will find a bunch of info




Sent from my Moto Z (2) using Tapatalk

Posted
28 minutes ago, mkeddie said:

Larger then stock is a wide range
Big mudders....big highway tires....35s.... 40s

Anytime u put bigger heavier tires on ur gonna take a hit 1 or 2 mpg
But can't say yet on my 2020 as I haven't bought the big tires yet

There is a few thread with tire size and mpg.... just search mpg u will find a bunch of info




Sent from my Moto Z (2) using Tapatalk
 

Thanks.  Yea I’ve looked at a lot of mpg threads and have yet to see anyone mention the 6.6 gas is at relates to larger than stock tires.  But being that my current duramax and every other truck I’ve ever owned had larger tires (usually 35’s in tread patterns from mild to full on mud tires), I am most certainly aware that it has an impact to a degree.  Just wanted to see if anyone had first hand experience with the new engine.  

Posted

I’m curious to this as well. Not buying a diesel this time. Have had 3. Just can’t justify the extra $ for something i don’t really need. I know this new 6.6 will pull all i need to pull. Only pull 15-20 times a year. All less than an hour away. Thanks

Posted

These trucks are heavy, the heaviest pickups yet built by GM, and while the 6.6 gas is a good engine it's not going to put them into sport truck territory.   Adding heavy, oversized wheels and tires will only make them more sluggish and hurt fuel mileage.  Anyone who tell you differently is not being honest.

Posted
7 minutes ago, unit said:

These trucks are heavy, the heaviest pickups yet built by GM, and while the 6.6 gas is a good engine it's not going to put them into sport truck territory.   Adding heavy, oversized wheels and tires will only make them more sluggish and hurt fuel mileage.  Anyone who tell you differently is not being honest.

Agreed.  I’ve owned 6.0’s in the past, so I’m familiar with the consequences in that engine.


Would still like to get feedback from anyone who has gone with larger than stock tire sizes on one of the gas burners

Posted

I was really happy with the height of my truck with the stock 275/65 R20s so I decided to wait.  Still want a slightly taller and wider tire in about 2 years.  I would also like new wheels as well with a slight offset if anyone has any suggestions.  Tks

  • 5 weeks later...
Posted

ill throw 295s on when 275s wear out.....I know they fit cuz another threw 305s on so shouldn't be a problem......since gas mileage is already crap whats 2 more mpgs, lol.....truck sits tall enough as is.....hopefully I get a few years out of stock tires, hard to throw away good rubber and don't have an issue with stock Michelins......actually was one of best rain tires I ever driven on in 2019 RST

  • 4 weeks later...
  • 3 weeks later...
Posted

they do great on hwy its only city driving that eats up mpg......the motor gets better and better every day it seems....at 3k mile mark and just seems to get more power  weekly....just breaking in i guess

  • 1 year later...
Posted

I put on 295/75r18 on the first day I got it,I did have to turn the tortion keys a couple of turns to eliminate rubbing issue. 2022 seems to have more space in wheel well than the 2017. My 2017 needed a leveling kit not the 2022. Not quite sure how it effects mpg since I only have 200 miles on it. But the speedometer is a little off because the bigger tires are traveling further each revolution. I’m not worried about mpg anyway. Looks better to me 

6A18F2D6-72BF-49E2-BC62-A1F331DCE4C7.jpeg

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