My 99 Sport 4.0 SOHC 4X4 has a 4.10 (4.11?) rear-end. To improve the gas mileage and reduce engine wear, I was wondering if anyone had an idea of the cost to change the gears to approx 3.00. I realize that quickness would be sacrificed, but if gas prices shoot up, the gas savings might payback the cost in 2 - 3 years. Thanks.

 

you would have to change the ratio in the front diff also. now you're talking $$$$ - the gas savings will never pay for it. with the overdrive transmissions these days your cruising ratio is OK anyway.

 

You do realize that if you went from 4.10 to 3.00 you would NEVER use 5th gear again right? Don't even think about towing anything or carrying anything more than yourself and a duffel bag either. If anything, and you do the gear swap yourself, go 3.73. If you do the gear swap yourself you are looking at about $250. If you pay to have it done, about $1000. Like the above poster mentioned, if this is 4x4, double those prices.