Hey all, My ax15 in my 91 is hard shifting, grinds going into 5th and grinds on the down shift into 3rd and sometimes 2nd. This tranny is completely rebuilt a couple years ago. The clutch feels good too. My buddy who used to own the rig sais he figures the throw out bearing is done, is this common? or is it prolly just the syncro going and the tranny is a scrap? thnks. great forum!


91 2dr 5speed. 4" rubicon lift. 31" ATs, 4000lbs warn, posi up front, custom roof rack.

 

What kind of gear oil your useing? If your running regular 80w90 gl4 contains sulphur it will attack the brass syncros resulting in tranny failure.I went through this same problem with a 97 tj with ax15.

 

if you clutch is engaging its the syncros

if you have any mechanical ability you can change them your self

 

I've got a good friend that rebuilds gearboxes, and he says the AX-15 is bad about eating blocking rings and syncros.

I've swapped my transmission oil over to the "syncromesh" lubricant that Autozone sells. It's a Penzoil quart bottle for like 7.00. 3.3 quarts is what it holds. I find smoother shifting now during the winter time when the gearbox is cold.

You'll probably have to have your box overhauled again- this time by someone who is compentant enough to go a good job, or at least get good aftermarket parts.