I have a jeep xj 89 automatic, that won't get above 35mph and it won't shift out of what I think it to 2nd gear. Also it won't recognize reverse or park. I can put it in any gear on the shifter from P-R-N-D-3-2/1. It it only goes forward and it won't shift. It has plenty of tranny fluid, and the exterior linkage seems to be intact. Where should I start looking now to diagnose the issue at hand?

Any and all suggestions are appreciated,
thanks Noah.

 

Block the wheels (so it doesn't roll away). Get under the jeep and check to see if shifter cable is hooked up properly.

 

Well I appreciate the suggestion. I have indeed smoked the tranny, but I am not sure why. I'm just gonna replace the trans.

 

how many miles are on it? when was the last time the trans filter was changed?

 

Test your TPS, one side is trans related. The late upshift is a common symptom of bad TPS. There are other electronics that control shift to test as well.. Do a search, these points were covered pretty extensive a while back in a thread.

 

The "filter" doesn't filter like an oil or air filter does.

It'a basically a screen against debris.

 

Things do wear out.

 

These transmissions have no filter to change. Just a simple screen to protect the valve body from debris should there be a catastrophic failure.

 

Now, back to the issue.

Click on the link in my signature and do Tip 1. All the grounds for the TCU are at the engine dipstick tube stud.

Do Tip 10 after that.

Also, remove and inspect the fuse under the dash for the TCU.

 

Do this AFTER doing the other Tips suggested, as the TPS also grounds at the engine dipstick stud.

The proper procedure for adjusting the tPS happens to be Tip 8.

 

Why do you say you "smoked" it? Your symptoms do not sound like a smoked transmission. Is there more information you have not yet shared?


Follow TJ's tips. You may be a few simple repairs away from being back in business, and it will be a lot cheaper than a transmission replacement that may not fix your problems.

Even if it is the transmission, see this post for a cheap cure that might save you a thousand bucks or so. It's worth a try.

 

230xxx miles. I found a different tranny/transfer case combo with only 165xxx that I'm in the process of swapping.

 

I think it is indeed the valve body. I am in the process of swapping tranny/transfer case (The change of the T-case is because the new tranny has a 23 spline vs. 21 spline output shaft to the T-case which my old one wouldn't work with.)

I want to tear open the old Tranny and see what went wrong.

 

I think some of the shifting is Mechanical/electronic. And it would shift mechanically with the help of vacuum lines. It's an 89 so it's older.

 

Huh?