I have the setup of 35's and 4.88's and I love it. I really wasn't interested in racing much, but I still got enough gear ratio to keep me slow on a pretty steep decline. I get about 17 MPG with my setup.

 

wow!!! 17mpg??? I get like 14 highway. If I drive like I want to I get 10 highway. You get 17?

 

Yep, I get 17 MPG when I drive to/from work (21 miles each way, 17 of which on highway). ...and that ain't the computer calculation either...

 

That I could live with. I, too, am not trying to turn my JK into a race car, just wanting as good or slightly better performance than stock. Mine is a 6 spd manual, currently running 2.5" BB and 33s. and I can't tell a performance or mileage difference from my stock Rubi setup. I may yet go with 4.88s if I decide on 35" tires. Thanks for your input. I realize not everyone's is going to be the same, and driving style has a lot to do with things, it's just good to hear some positive feedback from a real world situation.

 

I just keep telling myself - not all at once...or is that my wife saying - do not spend anymore money!

 

You gotta keep the economy going, tell her...

What's your take on the 35" tire situation? Do you have a gear change? What is your mileage like?

 

I am confused how the regearing works...can anyone explain this to me?

How can you get both a performance and gas mileage gain together?

If you lower gearing, don't you force the engine to higher RPMs to attain the same speed? Shouldn't that reduce gas mileage?

I am planning on regearing as soon as the money catches up(Northridge 4x4 is currently installing my lift).

 

The difference between 4:88's and 5:13's with an auto at 65 mph is about 100 rpms. i believe the extra "oumph" you get with the 5:13's is worth whatever negatives they offer.

corey d

 

engines are designed to run at certain RPM. You get outside that range and the mileage poops. Also the larger tire makes it harder to take off and burns more gas getting you moving. That is not taking in to consideration greater rotating mass, etc.

 

Hey WOL, Are you sure on this one? Not that I know differently nor do I have the means to check (6 speed) but my understanding was the PCM only used throttle position and RPM to gauge shift points.