Leaky trans and ugly noise (TH700R4) - Third Generation F-Body Message Boards

ChevyKen · 03-17-2002, 12:04 AM

Hey folks,
My first post in here I believe!
I don't know if any of you guys have been following my posts in the general tech / engine section - but I have had a series of problems with the 305TPI in my 86 IROC over the last few months. It seems like everytime something gets remotely close to okay, something new happens - and the last thing to start giving me trouble was the trans.

It is a TH700R4, and as far as I know it is stock inside out (except oil/filter of course). The car has about 88K miles on it.
A while back the trans had a period where it shifted very hard when put in gear. That is mostly gone, but it still is what I would consider "firm".
However, the last few weeks it has gradually started leaking more and more. In the beginning I just thought it was from around the pan, but when it started leaving drops/small puddles after every stop - I checked it out more closely. It seems to be coming from the drain hole in the dust cover underneat the TC.
The last two weeks the car has been sitting for a few days at the time due to other engine problems, and each time it has left a major puddle under the car (about 1-1.5 ft diameter) while not being started.
Today when I started the car and doing some mild revs, I heard some very disturbing sounds from underneat, kinda scraping/crunching kind of sound - and Im worried that it is something majorly wrong with the trans.
What are some thoughts on this problem, what should I check and so forth?? Am I looking at a complete rebuild, or replacement of the trans?

Any help or inputs would be greatly appreciated!!

Thanks,

Ken

Pro Built Automatics · 03-17-2002, 05:03 PM

The leak is from the front pump seal & wear at the bushing where it rides on the TC. With this many miles it might be time for a rebuild. Let me know if I can be of help?

ChevyKen · 03-17-2002, 06:41 PM

Thanks Pro Built!!
So, what are your thoughts about the noise heard while revving?

Also, from your username I gather that you are in the business? Shoot me an email if you think you may have what I need. My email is: chevyken@chevyworld.net

Thanks a lot!

Ken

ChevyKen · 03-18-2002, 06:38 PM

An additional question regarding a TH700R4 trans:

1. How much does one weigh
2. Who would be the best choice to use for shipping? Seems like UPS and FedEx don't ship things over 150 lbs.

Thanks a lot!

Ken

Bob86ZZ4 · 03-18-2002, 07:49 PM

I weighed my broken 700r4 with the torque convertor still in it (I can't get the darn thing off the input shaft, major failure here) and got 166 lbs. That was after I had the pan off for a few days draining as much fluid as possible.

ChevyKen · 03-18-2002, 10:07 PM

Thanks for the info, Bob!
Maybe if completely drained and with no TC it'll be within the 150lbs that UPS will ship.

Not sure yet if I will need a new trans, just preparing!
The car goes to the tranny shop on thursday, so I guess I'll know then.

Thanks again,

Ken

Pro Built Automatics · 03-19-2002, 12:59 PM

The transmission (700R4) weighs in at about 120-125 lbs. I use Alliance Air Freight. They charge $125.00 apx. from California to New york, and a less for shorter distances. The rates always change due to the increase or decrease in price of diesel fuel.

Kenwood · 03-19-2002, 06:51 PM

My vette tranny leaked in the same way...I agree its PROBABLY the Center pump seal...Because of the noise.....BUT mine was actually leaking from the O ring seal around the pump housing....I just pulled the pump and replaced all of the seals and its like new money.....BUT mine was not making any horrible noises...sOUNDS LIKE IT IS TIME FOR A REBUILD...