Mpg

i know its been posted before and i have done searches. i was wondering about 4.10 gears with 30 inch BFG Mt. i plan on going to 31's as soon as these wear out, but was wondering how the gas mileage would be affected, better or worse? and what kind of RPM i would be seeing on the freeway at like 65-70 mph. i have about 6,000 miles on the 30's so they wont wear out too soon, so i will have to live with with 4.10's for a while before i get 31's. its a daily driver, 2001 auto trans.

You'll love 4.10's and 30's.

CRASH

CRASH said:

You'll love 4.10's and 30's.

CRASH

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Coarse math puts that tire & driveline combo at approx 67 MPH @ 2500 (assuming true 30" and .8 overdrive) Stock is approx 73 MPH @ 2500

I've run 31" on the highway with 4.56 in a hi-mile 89 4.0/AW4 and it wasn't bad...I'd think that combo would be lots of fun in a fresh HO motor Jeep.

Depending how loaded down you travel with your Jeep, and the terrain you see most, I see nothing wrong with gearing lower than factory.

what kind of gas mileage have you guys seen or expect to have with this combo. thanks for the info.

My mileage in a beat 200k dd/trail pig doesn't equal your 2001 too closely, but mine gets/got 15-16 for lows and 19-20 highs. Didn't matter much going from 33" with 3.55 to 6" 31"-33" with 4.56. Way more fun to drive with the 4.56 though... especially with the 31"

i run 31's currently and will be switching to 4.56's soon... i can't wait! i know 4.56 is pretty low for 31's, but i hear its fun and i won't regret the change. i later plan on moving to 32's anyway. my advice is 4.10's are perfect for 31's, but if you ever want to go bigger (tires), get lower gears now so you don't need to keep swapping out gears.