Who has upgraded tire size from the stock tires/rims? I have a 09 sahara, 18" wheels and firestones w/ the 3.21 gear ratio. I currently avg. 19-20mpg's driving back and forth to work. I want to go a little more aggressive but not feel it on the tank? Anyone out there done similar, if so what are the results?

Thanks,
red

 

Bigger tires generally mean HEAVIER tires. I have 3.21's and can feel a loss of power between the stock 32" SRA's and stock 32" Rubi KM's. The KM's are quite a bit heavier and you can feel the lag. I personally wouldn't go any bigger with 3.21's ...

 

yeah what he said

 

Notice the two replies that said it was OK were 2-doors ... you JKU is heavier ...

 

I love this forum. So many people are asking the same questions I have.

I'm going up to a 285/70R/17's with mine.
It came with a 245/75R/16, if you can believe that. Where the heck did those tires come from?

 

You can try to minimize the impact of more aggressive tires, but you cannot avoid feeling in the wallet. Gearing and a programmer can improve performance an usually MPG to a degree, but you can buy a fair amount of gas for their cost.