Originally Posted by WILLIAMHALE1
I recently bought a 2012, wrangler, unlimited, altitude, automatic, with a 3.21 gear ratio, didn't do my homework. I plan on putting a 4" lift with wheels and 35" tires. Can I live with the 3.21 a while with the 35's or will it be unbearable, undrivable? Can I pull my boat with 3.21 gears and 35's? Should I re gear to 4.10 or 4.56 for mainly on-road use, boat pulling, light off-road, no rock crawling? What all will I have to change to go from a 3.21 to a 4.10 or 4.56? Just registered with wrangler forum today. Look forward to it
With 3.21 gears on a '12, you're gonna have issues with the 35's alone, much less towing.
On an auto, you'll find it wants to hunt and peck for gears when you go up hills or try to pass on the freeway. It'll kick in and out of OD constantly in those two situations. And that's without towing anything.
I'd recommend going to 4.56 gears. If you live in the mountains or do the majority of your driving in the mountains, I'd go 4.88.
There is a big difference between gearing needs for a 3.8L Jeep and your 3.6L.
Gonna run you ~ $1500 for a regear, depending on where you live. Find a shop that specializes in gearing, and order your gears through them (you want a master kit). That way both the mfr and shop warranties will be good. Yukon, Alloy USA, Superior and USA Standard all make good gears – and most gears are made by CHA Industries, so any of em will do.
There'll be a break-in period for the new gears; make sure you follow it religiously, unless you wanna pay for it all over again sometime down the road.
Here's a good thread on gearing. First page deals with the 3.6L Jeeps; 2nd and beyond deals with the 3.8L engine. If you really want a good understanding of gearing and how it affects your Jeep's power output, mileage, etc in all situations, read the whole thread.
Want 35s dont want to REGEAR ??