thm 400 problems
Thread Starter
2nd Gear
Joined: May 2003
Posts: 2
Likes: 0
From: zeelan
thm 400 problems
My 1972 Corvette has the original thm400 (38000 miles)but shows some problems.
In drive and low gear an unpleasant slipping noise comes from the transmission (or converter) at 1700 rpm if starting from zero.
I performed a so called stalltest (brakes on and accelerator to floor for some seconds) From 1700 rpm a yelling sound from transmission.
In reverse no any problem or noise, but engine rotates 2100 rpm. I think that is a lot!
Engine: standard 200 hp
Converter:o260o290 12o PJ7 RR
Oil is very clean, no deposits. I changed both oil and filter: no influence!
What can be wrong? Why do I have such a high stall rpm? Do I have to revise the whole transmission?
Please technicians try to help me
Kees
cagroeneweg@zeelandnet.nl
[Modified by 1972 freak, 8:37 PM 9/19/2003]
In drive and low gear an unpleasant slipping noise comes from the transmission (or converter) at 1700 rpm if starting from zero.
I performed a so called stalltest (brakes on and accelerator to floor for some seconds) From 1700 rpm a yelling sound from transmission.
In reverse no any problem or noise, but engine rotates 2100 rpm. I think that is a lot!
Engine: standard 200 hp
Converter:o260o290 12o PJ7 RR
Oil is very clean, no deposits. I changed both oil and filter: no influence!
What can be wrong? Why do I have such a high stall rpm? Do I have to revise the whole transmission?
Please technicians try to help me
Kees
cagroeneweg@zeelandnet.nl
[Modified by 1972 freak, 8:37 PM 9/19/2003]
Le Mans Master
Joined: Aug 2000
Posts: 9,662
Likes: 7
From: Semper ubi, sub ubi
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: thm 400 problems (1972 freak)
I don't have a clue, If I had to guess I'd guess that either your torque convertor has croaked or you have a stuck valve in in the body and aren't developing enough pressure inside the tranny. My reply was actually just to help you bump it to the top!
Welcome to the Forum.
Welcome to the Forum.
