Auto trans info Needed on 3rd gen

[Grenvilleter]

Apologies for originally posting in the 3rd gen forum. Perhaps I'll get a better response here.




Hi all…I have a ’97 ltd 4wd. Bought used . 185k KM's. I think the seller abused the tranny via towing somehow as he had recently installed a trailer hitch before i purchased. Anyhow…the oil looked burnt so I changed it a couple of times (drain &fill) without taking off the pan.

No issues for 20K until a day or 2 ago where intermittently, the tranny will not downshift into 1st gear when stopping in traffic.
Give it some throttle and slippage happens but when I pull the selector into 1st, the tranny then goes back to 1st gear and provided I put the selector back into drive, I can apply throttle and it up-shifts normally.

So…what’s happened? Can I correct this myself without doing a complete rebuild or swap?

Auto tranny’s and I are strangers in how they operate. I’ve been reading threads on complete drain and flushing but if I’m going to remove the pan, what should I look for that could be causing the problem besides crud in the filter.

Thanks

 

[TheeMikeB]

Do you have any local transmission shops that will do a free diagnostic on it? Like AAMCO or someone? They might at least give you an idea of what's going wrong.

 

[fourwd1]

OK, first of all, DO NOT take it to AAMCO or other chain trans shops, unless you have tons of $$ to piss away.
Now when you first changed the fluid you say it looked burned, did it smell burned too?
If so, you may have been on borrowed time. It wouldn't hurt to do some more flushing.

Your problem could be one of the shift solenoids. Have you checked to see what (if any) OBD-II error codes have been stored in the ECM? The CEL does not have to be lit to have a code stored.

 

[Grenvilleter]

Thanks for the suggestions.

BTW, yes the fluid also smelled burnt.
I took the truck over to a local trans guy who runs a home based business.

I described the symptoms and we hooked up a scanner and no codes showed up. We then went for a test drive with the scanner hooked up and everything performed flawlessly.

When the truck is cold, the problem is more symptomatic so the trans guy said to drop it off so he could check it out when cold.

As an aside note, I've really been trying to determine what is causing the problem but I'm going to try one last thing before I relinquish the truck to the tranny shop.

The tranny guy said these transmissions do not have a lot of material on the clutch packs (?) and usually when slippage happens, it does not take much to completely destroy them. He thinks my problem is not really serious yet and not in need of a complete rebuild.

I'm going to remove the pan and clean out the filter and replace the fluid for the 3rd time. Something I should have done in the first place but a question before hand-

The trans dipstick shows a fairly wide range of fluid level "OK" when hot. When I replaced the fluid the first couple of times, I drained into a pail and then added the same amount of new fluid back (or so I thought). The fluid is in the safe zone however it acts as if it is low in fluid.

Perhaps the fluid needs to be right at the top of the upper limit on the dipstick?

Another symptom besides being slow to engage when cold is, if I put the shifter into neutral while waiting in a drive-through line at operating temp and pull it back into D(rive), the downshift into first is very slow in engaging and I have to wait for perhaps 5 seconds before the transmission actually goes into first. I does seem like it goes into 3rd gear immediately and hence the potential for slippage occurs if I give it throttle. Almost as if I was low on fluid.

Anyhow, I'll drain , clean and refill one more time ensuring the fluid level is right at the top of the full mark when hot to see if the problem goes away and then if it still persists, I'll drop it off at the transmission guys place for another attempt at him finding the problem.