Tires sizes and fits

[Jabby]

What size and type of tire do you run??? I have the 6.0L with 4:10 gears and with the stock size tires the rpms are around 2300 at
100kms/hr I am thinking of going larger on my 03 2500hd in the hopes of improving mileage a bit. Any other suggestions or tips?

 

[Shredder]

I run 35/13.50/18 Dick Cepek FCII's on my 6.4. I ran both 33 and 35/12.50/18 Toyo MT's on my 6.0 and got better mpg with the 35's.

 

[BIGFOOT]

I have NEVER ever got better mileage with larger tires.... What have I done wrong ?

 

[GRD]

I have NEVER ever got better mileage with larger tires.... What have I done wrong ?

I was wondering about that... How would that work?

 

[couleeman]

I have NEVER ever got better mileage with larger tires.... What have I done wrong ?

Did you account that with the larger tire size your odometer and spedo are off? Also depends how much larger you go.

I have found that the actual is next to nothing. I ran 285's on my old ford 1/2 ton and that was a wash mileage wise.

I am running 285's on my current GMC and I have nothing to compare to as I didn't have 3 miles on the truck before the 285's went on...go figure.

 

[couleeman]

What size and type of tire do you run??? I have the 6.0L with 4:10 gears and with the stock size tires the rpms are around 2300 at
100kms/hr I am thinking of going larger on my 03 2500hd in the hopes of improving mileage a bit. Any other suggestions or tips?

By the way, what are you getting for mileage. The same rig, with 285's I am averaging 15, but most my driving is highway at 100kph.

 

[xsyourride]

What size and type of tire do you run??? I have the 6.0L with 4:10 gears and with the stock size tires the rpms are around 2300 at
100kms/hr I am thinking of going larger on my 03 2500hd in the hopes of improving mileage a bit. Any other suggestions or tips?

265's are the best to run.I had that on my 01 6.0l chev with 4:10 gears and I got way better milage over the 245's.the dealer can factory change your tire size up to 265's to make your speedo accurate aswell there is no rubbing on the wheel wells.With 285's you'll have to crank the torsion bars up.

 

[couleeman]

265's are the best to run.I had that on my 01 6.0l chev with 4:10 gears and I got way better milage over the 245's.the dealer can factory change your tire size up to 265's to make your speedo accurate aswell there is no rubbing on the wheel wells.With 285's you'll have to crank the torsion bars up.

Yes on the red, and I also had to trim the front bumper.

 

[Shredder]

I was wondering about that... How would that work?

The only thing I figured was that I run at a lower RPM at 100 kms/h with a little taller tire. Yes, I do drive like a Sally too; 105-110 kms/h on the hwy. On a GM you likely would see a decrease in mpg going to 35's, I think GM's only come with 31" tires from the factory. Fords come with 33's so going to 35's is not a big jump.

 

[77Crash77]

i have never gotten better mileage with bigger rubber. part may be caused by added width as well, resulting in increased rotating mass