Azriel

Hey guys, I'm in a bit of a situation where it seems the 3-4 clutch pack on my 700R4 has bit the bullet in my 88. I have a few options on what I can do here, and I wanted some input.

The transmission obviously needs rebuilt or replaced. I really don't want to take the car directly to a shop to have them rebuild it, because I don't have several thousand dollars to spend. So I can try a few things.

I can get a ~$200 kit on ebay and try rebuilding it myself in my garage.
I can get a 700R4 from a junkyard and hope it works.
I can get a rebuilt 700R4 from ebay.
I can take the tranny out and take it to a shop, to save the labor aspect of them taking it out.

Is there any other options? Is there any transmission I could swap in, like a 6 speed auto or anything, or is the 700R4 pretty much all I can use?

leesvet

Thing is this and you HAVE to watch this closely....

the 700R4 for the corvette uses different servos and valve body guts than the standard 700r4 that's used in several other GM models. Its EASY to end up with a plain 700r4 that shifts like a mini-van and there isn't **** you can do about it once its installed.
The Corvette rebuild kit is different than the GM HD rebuild kit.

So, IF you involve a shop or go to flea-bay you run the risk of getting a plain trans off the shelf and most shops don't know or CARE that there IS a difference !

I had a major chain shop try to burn me with this. Got my car back with over $2000 in work (and that's a small tag for elec controlled trans) and its shifting was so mushy that it was hard to tell it was upshifting and the downshift couldn't be felt at all. I had to raise 9 kinds of hell before they admitted that they used the standard rebuild kit and that they would have to go back IN to get it right. It got done, but it took an act of God to make it happen!
So, be careful.

Its not as scary as you might think. Get the factory manual, even the FSM has good detail on the trans and you CAN do it yourself. I watched a shop kid tear one apart and rebuild it, install it and drive it home the same day ! He'd never done a tranny before either. So if you have the tools and the place, go for it ! and DIY !

Good luck !

Azriel

Thanks! Any idea if I need any special tools for it? I don't want to have to take the whole engine out, can I drop the tranny through the bottom of the car?

My1st

Here's a good step by step right up. It's not that bad of job. It all comes out by component and back together the same way. Take your time and double check everything. http://www.bangshift.com/forum/forum...ld-tech-part-1

And this You Tube video.
Trans will come out the bottom but you need the car as high as you can get it. You may have to take the trans of the trans jack if using one to get the trans to clear for removal, I did. The tools needed you can easily make yourself.

Azriel

Thank you for this. Do you happen to know approximately how high I need to get the car to get it out? I think I recall reading the transmission was 18 inches tall... Which means I need a new jack if I'm going to get it out at all.

Strick

COST. It's all about how much you want to spend. I'm lucky, I found a truly great transmission shop that knows the 700 and 4l60e trannys. If I had an auto in my Vette, I'd have them add the upgrades to replace the weak areas in these trannys. To get an idea of what upgrades you might want to think about, try going to Mad Dog Transmissions and watch his video. I bought a 4L60E with the upgrades for my Jimmy and it is running great. Some have had problems with him, but not me. The video explains the weaknesses of the 700 and 4l60e trannys. Oh, how much did it cost? $1400 or so.

Cruisinfanatic

Dreading the day that my 85's auto just won't go anymore. If the car is not driven for a few days it will slip when just starting out. If I let the car idle for 15 seconds it does not slip.
Best to stay away from chain stores?

bley49

My 85 700r4 at around 101k started having shifting problems from 1-2 and so on I replaced it with a heavy duty 700r4 from monster transmissions although it took 5 weeks it was a great decision the shifts are very clean and consistent was $1200ish shipped you can pick out all your major components torque converter etc. And its built to order.

RF1

I would not recommend the first 2 options you listed.