Post Mpg With 265 Or 285 Tires

05 1500HD · April 12, 2011

Trying to decide which tires to get and I was wondering what is everyones MPG with the 265/75/16 or 285/75/16. I mainly drive city and right now I'm getting about 12mpg with the stock 245/75/16. Tires will be going on factory HD 16" rims.

Stevens03 · April 12, 2011

265/285 isn't going to be much if any difference on your truck. But you need to re-program for the which ever tire you pick otherwise your mileage results will be off. They may actually help your mileage some.

NickS · April 12, 2011

It wont help much, I get about 14.5 out of every tank, with mostly highway miles with my 285/65/18 and I have my blackbear tune set for this tire size. The city kills these trucks.

Mckenzie · April 12, 2011

285/75/16 Maxxis bighorn's

10-11 mpg short commutes with stop and go

14 mpg on the interstate with cruise on 70

Keep in mind though i have a heavy ass winch and brushguard, toolbox full of stuff, and two subs in my truck.

NickS · April 12, 2011

I hope your just joking about two subs pertaining to gas mileage?

Superperv23 · April 12, 2011

I hope your just joking about two subs pertaining to gas mileage?

I think he just is talking about weight wise, would add 100lbs or so depending on the setup

NickS · April 12, 2011

I realize that, but that is just stupid. That's like saying I get worse gas mileage when my wife or labrador is riding with me. 2 subs aren't going to make any difference in MPG.

centex · April 12, 2011

Davidb: I currently get 17-18+ mpg on the highway, not sure about the city, with 265/70/17 highway tires. Those are balding and my next set will be 285/70/17 nitto terra grapplers, so I am curious as to what the mpy city/highway will be with those.

But I am sure if I take my sub/amp out I will automatically see a 1-2mpg increase.lol

2006 Gmc Sierra SLE 1500 2wd. ext. cab, I also went from 245 stock to 265, never really checked mpg, but am pretty satisfied with 17-18+ with bigger tire.

Stevens03 · April 12, 2011

The OP's truck is a 1500HD with the LQ4 6.0L. Big difference over the 5.3L numbers.

NickS · April 12, 2011

Oh, didnt see that. My old '03 1500 HD would get 11-13 no matter how I drove it. That 6.0 likes gasoline. I don't remember what size tires I ran, but it was larger than stock, but not as tall as a 33". I had to tighten the torsion bars to keep it from rubbing.

SpeedyV · April 12, 2011

I'm running 265s (BFGs) on my '03, and I've seen anything from around 10.9 to 12.7mpg on the DIC in mixed driving, which translates to low-11s to low-13s when corrected. I probably can't expect much better when commuting with a heavy truck (4WD, 4WS, all options + 270lb driver). Scheduled for a BB tune next month...

rgv · April 12, 2011

Trying to decide which tires to get and I was wondering what is everyones MPG with the 265/75/16 or 285/75/16. I mainly drive city and right now I'm getting about 12mpg with the stock 245/75/16. Tires will be going on factory HD 16" rims.

after factoring in the 3%-4% difference in your speedometer/odometer with each step up in size, you will lose negligible fuel economy by going to a 265 or 285 in the same tire type and tread style

the bigger difference comes in when you swap out rib-type highway tires for relatively heavy and agressive 'off-road' type tires.

Having said that, 285's on a stock 6.5" wheel will give you poor tread life (in the center) if you inflate them where they should be, and will hurt fuel economy and handling if you air them down to sit flat.

SpeedyV · April 12, 2011

after factoring in the 3%-4% difference in your speedometer/odometer with each step up in size, you will lose negligible fuel economy by going to a 265 or 285 in the same tire type and tread style
Having said that, 285's on a stock 6.5" wheel will give you poor tread life (in the center) if you inflate them where they should be, and will hurt fuel economy and handling if you air them down to sit flat.

Speaking to this...I had a 2500HD with the 8.1L/Allison combo and 285/75R16 (stock rims), and I achieved better economy than my current 6.0L truck with 265s. Both had 4.10s. But the Allison had an extra gear over the 4L80-E, that truck was 2WD, and that motor had plenty of torque to go around. Loved the look of those 285s.

Also, I had nice, even tire wear and a decent ride running 55psi front/45 psi rear on that truck (unloaded). I'm running 55psi all the way around on my current truck (unloaded) and wish I would see better mileage because of it.

Two things will keep me from going to 285s on the 1500HD: (1) I don't want to see any further drop in economy, and (2) my '03 Sierra 1500HD has nowhere near the amount of clearance that my '01 Silverado 2500HD had around the front wheels. I'm close to rubbing with the 265s on the Sierra, while I barely had to crank the torsion bars on the Silvy to avoid rubbing at full lock in reverse. I could maybe go to 285s on the Sierra with a 2" lift...

Mckenzie · April 13, 2011

I hope your just joking about two subs pertaining to gas mileage?

the subs, the box, and the amp combined are pretty heavy...just throwing out there any stuff that might affect the mileage

NickS · April 13, 2011

If that effects mileage, then I guess I won't let anyone ride with me, take out my amp and subs, hell I'll take out the factory speakers while I'm at it, toolbox, bed mat, and I guess my receiver hitch. That thing weighs like 10lbs. I should be getting 20+ MPG then? Your amp and subs cannot possibly effect mpg's.