Help,

Will 3.31 gears in my 97 F-250 with the 5.8L gas improve my mpg?
I have 4:10 now and get 13.4 if I baby it.....

Thanks,
Michael

 

Maybe. but if it does, it will be marginal. Even if it did give you a decent increase in MPG, have you worked out the numbers? Have you taken into account that you would have to drive QUITE a bit of miles before those new gears would pay for themselves? You are looking at about $1700 for a gear swap. Being that that truck is already getting up there in age, do you really think you would keep the truck long enough to see a worth while savings in fuel? For me at least, it would have to be a very sizable amount of $$$ to make it worth my while, especially when you weigh into account the big loss in power you will see...

 

I had a '95 F150 that came with 3:55's and I changed to 4:10's and the mileage stayed the same. That change to 4:10's really woke that truck up, best thing I ever did to that truck.