Anybody...on a '94 Grand Cherokee, 5.2 liter, 4X4, how do you tell what the ratio is for differential replacement? I have a Hollenders book but the numbers I found on the front differential cover bear no resemblence to those in the Hollander book. thanks!
Usually there are two numbers on the tag... number of ring gear and pinion teeth. Divide the big number by the little one. Example:
43 / 14 = 3.07-- JimG
80' CJ-7 258 CID 35" BFG MT on 15x10 Centerlines D44 Rear, Dana 30 Front. SOA 4.56 Gears, LockRight F&R Dana 300 w/4:1 & Currie twin sticks Warn X8000i w/ dual batteriesForgot to mention... the numbers are usually on a tag under one of the cover bolts.. not on the housing itself.
JimG
Jack up one back tire and then tape a peice of string to your rear driveshaft. rotate the tire once, and then see how many times the string has wrapped around the driveshaft. Not precise but you could modify this method to be more accurate. Nick
If you turn the tire twice, you get an accurate count of the ratio. Only one tire in the air though.
For two turns of my rear wheel, my drive shaft spins 3 and 1/3 or so turns meaning I have 3.31 gears.
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT'sNick N wrote:
On Sun, 12 Oct 2003 09:44:52 -0400, Mike Romain shared the following:
For two turns of your rear wheel? I thought one (instead of two) complete revolution of the rear wheel would result in 3 1/3 or so turns of the driveshaft if you had 3.31 gears. Can you please elaborate on the "two turns of wheel=3.3 turns of driveshaft=3.31 gears"? Thanks.
-- Travis
I have an open diff so with one wheel on the ground stopped, the wheel in the air turns twice to get the ratio.
Same deal if stuck on ice with only one wheel spinning, that one wheel will be going two times faster than the speedometer says. So if you are spinning 50 mph on ice, that one tire is doing 100 mph!
Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's
Rotate the tire *twice*. You're going through the spider gears. If you have a limited slip or a locker, you have to jack up the entire rear end to allow both tires to rotate together. Then you rotate once.
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