91 YJ - Tran/Rear Diff - Rebuild - Thoughts/Help Needed

  • HTML tutorial

infennonlabs

Rank II
Launch Member

Traveler I

91 YJ - Tran/Rear Diff - Rebuild - Thoughts/Help Needed

Here's the scoop:

Vehicle:
91 Jeep Wrangler YJ 2.5l 4cyl
(I believe) stock differentials and transmission:
Dana 30 or 35 (don't really know and not sure on gearing)
AX-5 Transmission
(I believe) 2.5" lift and 31" tires

What happened:
Was on a long roadtrip, on the way home 5th gear was sounding pretty bad, grinding etc
Almost made it home, was doing around 65-75 (speedo isn't set correctly) and could start smelling fluid heating up. Large clunk and lost all 'power' in 5th gear. Dove to the shoulder to have smoke come up from the shifter and fluid drop from the transmission and it looks like the rear differential too.

What are my options?

Would love to hear thoughts on the problem as I have no idea where the total failures may be and if anything is salvagaeable. I'm assuming worse case scenario: Need a new clutch, transmission and rear differential. Assuming at that the cost would be from $5-$10k.

Although I don't want to spend a bunch of money I think I'm invested to fix it (even though I have the weak jeep etc) I've started looking for donor vehicles but also just thinking of going the route of buying new parts to upgrade things like the differential (although I'm somewhat confused on fittings)

Thanks for reading any providing any thoughts.
 
Last edited:

JeepWave

Rank V
Member
Investor

Enthusiast III

1,964
Broomfield, CO, USA
First Name
Eric
Last Name
Hutchins
Member #

9083

Ham/GMRS Callsign
W0EMH
If you need a new trans and rear diff, you could look at local junkyards to see if you can find a donor Jeep. I’d look for one with the AX-15 trans because you may as well upgrade that—I’ve not done it myself but understand it’s a straightforward swap to do. You may want to check the driveline angles, in case the lift created too sharp an angle from the transfer case to the rear diff and contributed to the failure. Possible that a new driveshaft is needed too, if that’s the situation. Of course, beyond a certain point it may not make sense to repair, since used TJs can be had for around $5K with a little detective work. Good luck!
 
  • Like
Reactions: infennonlabs