So yall have probably gone over this a million times but I was curious.... I am thinking of re-gearing my rear axel on my cherokee. The question is to what ratio I should go? I have 31's on it. I have the stock chrysler 8.25 in it so I'm lookin for a bit more power. I was thinkin 4.10's but I didn't know if thats too much. It's also only 2 wheel drive so I dont have to worry bout re-gearing the front as well to match.

I'd like to know what is in there now. A 2 wheel drive with 31's and a 3:73 runs REAL good.
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

it's the stock chrysler 8.25

Uhhhh Yeah I got that. Now what is the gear ration in that eight and a quarter?
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

RG DIAMETER 8.25"
10 3/18" X 24 LH THREADED BOLTS
PINION DIAMETER 1.626" 27 SPLINE
CASE: 2.71 & NUMERICALLY HIGHER

8620 Material Heat-Treated

Assembly Specifications:

Cover Bolt Ft. Lbs. 15-25
Pinion Brg. Preload In. Lbs 10-20
Pinion Brg. Preload In. Lbs Used 10-15
Ring Gear Backlash .005-.008
Ring Gear Bolt to case Ft. Lbs. 75
Side Brg. Caps Ft. Lbs. 100

As it is 2wd and you are looking for "power", the simple solution is to go to 4.10 which would give ou a better towing/hauling capacity.

ok, so either 3:73 or 4:10 ?? I'm lookin for some good power cus I might be trailoring a couple jet skis here soon.

I'd still like to know what is in there now.. I guess you have no idea, have you?
You can do the "count the turns" trick. Go jack up one back wheel... Put her in neutral with the brake off... Now With chalk or something you can see make a mark on the tire near the ground and another on the driveshaft..
Ok now turn the tire ONE TIME around while counting the turns on the driveshaft. And there you will have the existing gear ratio. The driveshadt will turn either 3 times or 3-1/4 times or 3-1/2 times or 3-3/4 times or 4 times.
You should FIND OUT what is in there before making a firm decesion on what to purchase.
My opinion a 4:11 in a 2 wheel drive with 31 inch tires is too low! I wouldn't go over 3:73 if it were me. And I may just opt for a 3:50 depending on what is in there now and how much it lugs.
REMEMBER rpm equals gas burning!
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />

It is my understanding the XJ came with these combinations

-- 3.07:1, manual transmission, I6 engine.
-- 3.54:1, automatic transmission, I6 engine with DANA 44 rear differential.
-- 3.55:1, automatic transmission, I6, V6 engines; manual transmission, I4 engine.
-- 3.73:1, automatic transmission, I6, Tow Package, UpCountry Package.
-- 4.10:1, manual transmission, automatic transmission, I4 engine.
-- 4.56:1, automatic transmission, I4, offroad or tow package.

Generally, the acceptable RPM range is 2000 to 3000. The optimum RPM range is 2300 to 2600. (based on 55-60 cruising speed.)

Either 3.73 or 4.10 will give you the towing capacity. With over 30" tires, I would opt for 4.10. Under 30", I would opt for 3.73.

well, thanks for the stats and you are right. I searched around and found a website with all the jeep cherokee specifiactions from transmisions, to engines, axles, driveshafts, transfer cases and so forth. I have 3.55 gear ratio