Texxas

I have a 74 Big Block with an overdrive transmission..TH-700 I think..anyway when I bought the car 3 months ago the tranny came installed with it.

My problem is this...the car shifts fine from 1st to 2nd, however it slides big time from 2nd to 3rd and again from 3rd to OD. The engine has 500 miles on a complete rebuild and is running great.

1. What could be the problem? I am not mechanically inclined and want to find out what you all would guess the problem is and offer suggestions for fixing the tranny.

2. Additionally can any transmission shop work on this transmission or should I take it to a vette specialty shop.

3. Finally would you all recommend putting a TH-350 or 400 transmission back into the car? I am more interested in performance and reliability than gas mileage as this is my playing around car.

Thanks all!!!!

Texxas
'74 454
:blueangel:

Stingy74

First off, somebody has gone through all the work to put the OD transmission in your car so i'd keep it that way. I don't know much about transmissions but isn't there a band for each gear that could possibly slip? Like I said, this isn't my area of expertise so take it with a grain of salt. You might wanna get ahold on 45ACP here on the forum. I think he used to manage a transmission shop.

Texxas

Thx Stingy.

Anybody know how to get in touch with 45ACP?

Texx

45ACP

I'm afraid I didn't manage a tranny shop, I managed a machine shop that rebuilt torque converters.

If I could help I sure would, but I did not absorb enough tranny stuff to be of assistance.

Fortunately, there ARE some guys here with hands-on experience with 700's!

Techno

Heres an easy check, if its there.
Pull the vacuum hose off the vacuum modulator and stick a q-tip up the hose. if there is tranny fluid on it then the modulator is shot. This is just an unbolt re-bolt item and is cheap & easy. I think it would be on the right side of the tranny and the hose would attach to a major fitting on the intake. But being an OD I don't know if they still use them.
This controls the shifting and hopefully is what is wrong.

I forgot, the vacuum hose could be off a little or have a hole too.


[Modified by Techno, 3:17 AM 12/8/2001]

Texxas

Thx amigo :)

T

Texxas

Thx techno!

Texx

Tx73Vette

Hey Chris havent heard from you lately was wondering how your car has come along. Give me a call at 972-539-6407.
I got layed off at my jab about a month ago, But Im working for a company in Flower Mound only 5 minutes from my house

Texxas

Trust everything is going well bud! Tried to email you twice and let you know that the vette is here...let's hook up tomorrow and go for a ride!

CC

lyonsh

In addition to what Techno told you, check the fluid level. Drive the car enough to warm it up, then park on a level surface and leave the engine running. Check the fluid level on the dipstick. If it's low, that can cause the slipping.

Also, smell the fluid on the dipstick. If it smells like burnt popcorn, your tranny has been overheated and the fluid has lost its viscosity. If that's the case, it's time for a fluid (and filter) change.

Jvette73

If your trans is a 700r4 then it does not have a vacuum modulator. 700R4's use a TV cable connected to the carb linkage to controll pressures and shifting. I would check for proper operation and adjustment of the TV cable. and of coarse as mentioned above, the fluid level. With a correctly adjusted TV cable, the car should kick down from second to first at a very slow speed. Put the car in drive. Move forward slowly just untill the car shifts into second. When you are sure that you have the car rolling at its slowest possible speed for second gear, floor the throttle. The tranny should downshift to first. If it doesnt, either the TV cable system is messed up or its out of proper adjustment.

Texxas

Thanks everyone for the responses..the tranny is a 700r4 btw..my mistake before.

Assuming I do need to take it into a shop for work...can someone give me a price range for potential repairs and any additional things to have the shop look for?...Just don't wanna get hosed.

:)

Texx

Tx73Vette

Sure Chris give me a call or better yet give my leave your number on my recorder and I will call you or e-mail me at tx51dm@aol.com.
Talk to ya latter and cant wait to take a ride in her.