Auto Transmission Question

[Guest dapy]

My 1989 has the GM 305 engine with the standard automatic transmission. The transmission is slow to release when stopping and occasionally the engine dies. Moving into neutral before stopping solves the problem, but I would like a more permanent solution.

Edited March 26, 2014 by dapy

[Gunslinger]

It's a standard GM tranny, so any competent shop should be able to diagnose that. It might be a vacuum modulator but that's just a guess on my part.

[mfg]

I don't understand what You mean by "transmission is slow to release when stopping". It doesn't automatically shift down to first gear?

[Avanti83]

Your tranny should be a GM auto with overdrive. My guess is the torque converter is not unlocking as quickly as it should. Most any trans shop should be able to quickly diagnose it.

It's to early for computer control, but you might want to try changing the fluid and filter if you are doing it yourself and/or google torque converter unlocking. Your tranny should be a 4L60 version of the 700R4. I'm betting on converter locking/unlocking issues.

[bigdaddy]

I agree with the converter answer. Had 1 like that about 10 years ago, ( killed the engine @ a stop). The converter was trashed. This was on a 200 R4. I wouldn't continue to drive it until it is checked out, it's probably putting some heat in the tranny . Good luck.

Edited March 25, 2014 by bigdaddy

[Guest dapy]

Thanks for responses. Will have it checked today. Isn't there a computer connection between how the tranny works and the engine stopping?

How extensive is it to repair or replace the torque converter?

Edited March 26, 2014 by dapy

[Avanti83]

Thanks for responses. Will have it checked today. Isn't there a computer connection between how the tranny works and the engine stopping?

How extensive is it to repair or replace the torque converter?

Probably not worth repairing, replacement requires unbolting the converter, removing the trans, replacing the converter and bolting the trans back on. The only problem is the weight of the trans. I put one in my 83 on jack stands and a HF tranny jack. It's fiddley. Rock Auto shows the converter (1989 Camaro) at $69-92 + core

Lockup control is electrically actuated. Here's the wiring diagram from 1989. Hope it helps.

http://www.rowand.net/Shop/Tech/images/TH700R4WiringDiagram01.bmp

Google is always a great help on these issues, I use it almost daily. Good luck, Bob

Edited March 26, 2014 by Avanti83

[Guest dapy]

Assuming the problem is the torque converter, and you say a replacement part is not very expensive, and the car is on the transmission repairer's lift is the replacement time and price not worth doing? I am mechanically challenged, but there are lots of tranny repair places nearby. This kind of help is what makes this forum worthwhile.

[Avanti83]

You are essentially driving a 1989 mid/full size Chevrolet, although much better looking. Personally, I'd ask around about a local shop that does "older" cars, of that era that is trustworthy, by reputation, and go talk to them.

Take 'em for a drive, be sure they know the trans and engine are 1998-99 chevy and let them diagnose it. You are far enough into the diagnostic era that they should be able to tell what the problem is in short order. Let them give you a quote and if it's reasonable, repair it. If they want to rebuild the tranny then I'd get another opinion or two. A rebuilt 4L60 is probably $900 or more.

I'm just not one to throw parts at a problem if I have to pay the freight. If it was mine, I'd just throw in a converter after I made sure I had a 12V signal to the connecter on the tranny that gave a signal when it should and see what happened but my labor is free so I'd only be out $70 or so. If they replace it after diagnosis, you'll probably have $300 in labor but the problem is solved. They may also know that there may be an answer from their experience that is a $25 connector and save you more.

An on-site analysis is always better than on-forum but I think you now know the correct questions to ask to find the right shop.

I hope that answered your question, if not, I'll try again. Bob

Edited March 26, 2014 by Avanti83

[wdaly]

I had this same problem with my '88 over 10 yrs ago. Right now I can't seem to find the paperwork. Your transmission may not be the same as mine, but I went to my mechanic and he referred me to his 'go-to' trans shop. They immeadiately knew it was a 'well known' GM small part problem (that GM engineering changed later). $1000 and no trans problems since (and I occasionally tow a trailer). I'm thinking if you were to go to a Caprice Forum you may find a quick & easy answer!

[Guest dapy]

The transmission shop has diagnosed the problem and will replace the torque converter and reassemble (fluid, gaskets, etc.) for $350. Two hours labor. That sounds reasonable to me. Probably time to drain and refill the tranny in any case.

Edited March 30, 2014 by dapy

[Avanti83]

$350 to me sounds about par for the course. If you get a chance to try to bench the tranny when they have it out, you'll think that money is well spent.

Take a look at the rear seal where the drive shaft yoke is inserted, It's probably a good time to replace it also if it has never been done. Seal should be under $20. Also look at the speedo adapter, if you see any signs of leakage, there are two O-rings that can be replaced. The O-rings can be done anytime so unless they look like they are leaking, I'd leave them alone.

Glad it was straight forward and not the tranny. Bob

Edited March 30, 2014 by Avanti83