Tire size vs Gas mileage????????

buddman (AKA Mick) · March 08, 2013, 11:41:37 PM

K, question is this. Right now I got 31 10.5 15s. Have a set of 32 11.5 15s in better shape. I know ther lil bigger n heavier, but will lower my rpm's at highway speeds. How will this affect my gas mileage?? Just lookin for sum input?

lilred · March 08, 2013, 11:50:05 PM

It's all in the gears. I have 33's on a gmc jimmy with 4.56 gears, gets as good if not better than a stock jimmy. But yes, uping tire size without changing gears is going to suck the gas down unless ur driving a diesel. Actually looking to up my tire size a lil more, 3 grand on the eway is a bit much. lol

4x4xdodgeman · March 09, 2013, 02:27:34 AM

you are only taking 1" both ways. run them

betterbeaters · March 09, 2013, 03:14:22 AM

Quote from: 4x4xdodgeman on March 09, 2013, 02:27:34 AM
you are only taking 1" both ways. run them

Merc09 · March 09, 2013, 04:24:47 AM

not a big difference not even noticable

buddman (AKA Mick) · March 09, 2013, 04:58:14 AM

See I runnin like 2300 rpm on highway at 75 was thinkin taller tires lower rpm. N help. Oh n it a 1999 ZR2. Stock gears as far as I know. Jus got it.

lilred · March 09, 2013, 05:10:16 AM

you probably get 15-16 now, expect to see 12-13 with 32's

lower RPM's help to the point where the engine is constantly lugging. 2300 on the eway is pretty good for a 4.3

Merc09 · March 09, 2013, 06:32:32 AM

I went from 262/75/16 to. 33x12.5-16.5 and I got 24 highway and I still get 23-24

burl · March 09, 2013, 12:54:35 PM

I run 1800 on the e way.. At 65 lol zr2 also, im goin to pit 32s on mine if I can find some rims I only get 10-12 mpg any ways

buddman (AKA Mick) · March 09, 2013, 03:17:24 PM

U seem 2 be the S 10 God lilred, lol I mite try em if I still have an extra set of rims just 2 see I guess. Unless I come acros a good set of 31's. Thanks 4 the input guys.

lilred · March 09, 2013, 04:28:38 PM

lol

& merc09 full size is a different story. 4.3's don't like extra work

atleast the zr2's have 3.73 gears, that will help a little. I get 16.4 on average if I stay below 70. What was really bad was going from 225/60R15's on the sonoma, 2.5L 5 speed, to 31/10.50's, it went from 28mpg to 19.

Merc09 · March 09, 2013, 04:46:05 PM

Quote from: lilred on March 09, 2013, 04:28:38 PM
lol & merc09 full size is a different story. 4.3's don't like extra work atleast the zr2's have 3.73 gears, that will help a little. I get 16.4 on average if I stay below 70. What was really bad was going from 225/60R15's on the sonoma, 2.5L 5 speed, to 31/10.50's, it went from 28mpg to 19.

yeah I guess your right and holy crap loosing 9mpg isn't worth that for me lol.