Gear ratio? Maybe new rear diff?

[kaylaah]

I bought a 96 grand Cherokee and it needed the front differential changed.. So we changed it (it came from a grand Cherokee a few years younger) and now if we're moving it around when we put it in reverse it it seems like it wants to fly backwards. I was told the gear ratio is probably different and that if it isn't fixed its really bad. Any thoughts on this? Do I need to change the gear ratio? If so how is that done? Or should I just change the rear differential too?

 

[TerryMason]

Someone with more information about Grand Cherokees can chime in here, but generally speaking, having different gear ratios in your front and rear differentials is bad - bad as in destroying your transfer case if you run it in 4 wheel drive.

Assuming you have different ratios, you'd probably want to decide which ratio to stick with, either what's in the front, or what's in the back. If you want to get larger tires, or have already upgraded, you'd probably want to stick with the larger gear ratio.

look on the diff cover for each axle and see if there is a metal tag on it. It should say the gear ratio there.

 

[kaylaah]

Someone with more information about Grand Cherokees can chime in here, but generally speaking, having different gear ratios in your front and rear differentials is bad - bad as in destroying your transfer case if you run it in 4 wheel drive.

Assuming you have different rations, you'd probably want to decide which ratio to stick with, either what's in the front, or what's in the back. If you want to get larger tires, or have already upgraded, you'd probably want to stick with the larger gear ratio.

look on the diff cover for each axle and see if there is a metal tag on it. It should say the gear ratio there.

So if I just use it at rear wheel drive it will be okay? Well check the gear ratios tomorrow, where abouts are the metal tags located?

 

[69jeepcj]

If your cherokee is all time 4wd (AWD) It will distroy your tcase also. Same as putting it in 4wd. The tag for the ratio should be under one of the differential cover bolts. A slight differance is sometimes ok, I think it was ford that used to use slightly dif ratios in there difs, but is was the differance of like a 354 gear with a 355 gear, very close. I would have it fixed asap!! If you cherokee is not AWD, and you do not use 4wd then Yes you can drive it and it should be just fine.

 

[Bounty__Hunter]

It can also destroy the transfer case if the axle ratios do not match when in 2wd, don't take any chances, don't drive until it's verified.

 

[kaylaah]

If your cherokee is all time 4wd (AWD) It will distroy your tcase also. Same as putting it in 4wd. The tag for the ratio should be under one of the differential cover bolts. A slight differance is sometimes ok, I think it was ford that used to use slightly dif ratios in there difs, but is was the differance of like a 354 gear with a 355 gear, very close. I would have it fixed asap!! If you cherokee is not AWD, and you do not use 4wd then Yes you can drive it and it should be just fine.

Mine is awd. So if I take the driveshaft off and drive it like that then that's bad?