1992 Toyota 4-Runner Tranny Problem

[inVERt'D]

I'm not too knowledgeable about automatic transmissions in general or Toyotas in particular, so I'm hoping here could give some helpful suggestions.

1992 Toyota 4-Runner, V6, 4WD Auto

My brother recently purchased a 1992 Toyota 4-Runner as a recession fall-back vehicle. It has a number of issues, but the main one of concern at the moment seems to be the automatic transmission. The previous owner was told that the tranny was slipping and needed a minor rebuild with some new seals--for like $800.00. This ain't happening.

Here is what I have observed so far. When in "Drive" it seems to start in 3rd gear, and can be reluctant to downshift. However if manually shifted into 1st or 2nd, those gears work well. On one occasion I was testing it with a rather heavy passenger, and when going up some small hills in Drive, it would come out of gear completely, then go back in just as suddenly. It didn't feel like slippage to either of us (and he's pretty savvy about older vehicles), it was more of an on-off thing. On the way back up a much larger hill this didn't occur at all.

I'm inclined to wonder if it might be a problem in the ECT/ electronic transmission control. I have wondered about the the neutral safety switch, but it can can be shifted manually.

I have an OBDII/CAN scanner, but this vehicle needs OBD "I."

Any suggestions for diagnosing/ fixing it would be helpful.

[BillyGoat]

Has the truck sat unused for a long time? That's not good on auto trannys.


From what you described it sounds like you need to have it rebuilt. Shifting by itself, yeah, you've got bad o-rings and seals.

You can save money by R & R the tranny yourself. I.E. you pull it and put it back in.

[inVERt'D]

I think it was a second car for the PO, so it may have sat awhile. It has almost 200K miles on it, so it seems it was driven a fair amount too.

Thanks for the input about the o-rings and seals. I was planning on doing the R&R, and had even contemplated doing the rebuild if it turned out to not require too much in the way special tools (jigs, etc.) or PITA factor. I just don't want to waste money or do all that work only to find out the problem was in the ECT or something.

[Zoobi]

We used to have an issue with the shift solenoids in older "electric shift" trannies. They could stick. With something that old, like billygoat stated, even if you had solenoid issues, you will have worn orings and seals. At least it dosnt slip or make wierd noises. That means it's probably worn out and not broken. Even with an "ECU" problem it still has 200k on the tranny. I tell my students all the time, more often than not, with a high mileage vehicle, you have more than one problem causing the customers complaint

Unless you have the experience and the tools to rebuild an auto, have it done by a shop.

Scott

[inVERt'D]

This reminds me of why I suggested to my bro that we convert it to manual tranny. I was only half kidding.

[TJ Jake]

I've heard of XJ's having the same problem (they have the same tranny) and it was just as simple as the plug on the TCM coming undone.