I just bought a '93 LC with 35 BFG AT tires and will be doing a OME 2.5'' lift soon, thinking of regearing to either 4.56 or 4.88. I do a lot of highway driving but will be doing some offroad as well. How will this affect performance particularly MPG?
4.56 will give you the best mileage, 4.88 more pep. Stock gears are actually pretty good for highway mileage w/ 35s, assuming you are on relatively flat roads or not at high altitude.
Yep, 4.56 best highway mileage. 4.88 if you do any wheeling beyond just overlanding. 4.88 if you are at altitude or pull a trailer, or need to go up lots of hills, or have a heavy rig.
Try it with stock gearing for a while. I've always thought 35s and the stock 4.10s was a great combo. If you are at elevation, though, it may be a different ball game.
I have 4.88's and 35's and like them on the highway due to climbing hills in top gear without frequent downshifting. The torque converter remains locked almost all of the time.
I've got 4.88 on 35's as well. Great combo. Maybe better mileage with the 4.56, but if you do hills or off-road, you're gonna hate the power loss.
The 4.88 give it an almost stock power deliver and even the speedo is only a few percentages off.
Good luck!
35's on stock gears, on the freeway, at altitude, climbing long grades... it's miserable. And it's like telling your geriatric transmission to break dance.
Try it with stock gearing for a while. I've always thought 35s and the stock 4.10s was a great combo. If you are at elevation, though, it may be a different ball game.
I've never heard of anyone changing the tranny for bigger tires.
I did my axels not just for ratio, but also strength and adding air lockers.
I'm happy
When they go on sale you can buy an entire kit from @justdifferentials for a little under $1k. I think last year around black Friday it was $900 and free shipping. If that deal was going on right now I'd have my kit in the mail. Of course, i'm not sure what I would do with said kit as I've never installed gears before. And there in lies the problem, you have to pay another $1000 to ship them to someone who installs. Although I believe they will ship you a complete third member with your gears of choice.