The TH400 in my 79 has an output spline that is drilled & tapped, as it came from a truck. Uses a std car yoke & doesn't leak. It must be right - cause Bubba did it that way!
Turbo 400 Application?
Thread Starter
Burning Brakes
Joined: Sep 2005
Posts: 895
Likes: 4
From: whitman massachusetts
Turbo 400 Application?
This turbo 400 transmission was given to me and I would like to have it rebuilt and put in in my 1971 roadster project car. Could anyone tell from the photos if there is a reason not to spend the money on a rebuild. It is my understanding that as long as the transmission is a shorttail they are all the same. Were the Corvette turbo 400's unique? Any info on this is appreciated!
Melting Slicks
Joined: Jan 2003
Posts: 2,877
Likes: 13
From: Doha
St. Jude Donor '08
TH400 for chevys are all the same, and yes it seems you have the correct tail for the C3 applications. Rebuilding a TH400 is not a big deal, I did it myself and it was my 1st time ever to work in a transmission, now its working fine and shifts firmly. Good luck!
Le Mans Master
Joined: Aug 2003
Posts: 7,720
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From: Chattanooga TN
NCM Grand Opening Veteran
Joined: Sep 2005
Posts: 20,979
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From: South of giving a damn
St. Jude Donor '11, '17
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
THM400 is a good, reliable transmission that can handle lots of load. It also is very un-economical if you do a lot of driving. If you have it rebuilt, you can try it to see if it works for you. You'll have not problem selling it, if it doesn't.
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Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
TH400 are really tough.
As for that freebie ... if there's no known bad history ... if its fluid looks & smells OK ... & pan-filter ain't filled w/ bits ... it may not "need" rebuild. Chances are new front & rear seal & new tailshaft bushing & filter will suffice.
As for that freebie ... if there's no known bad history ... if its fluid looks & smells OK ... & pan-filter ain't filled w/ bits ... it may not "need" rebuild. Chances are new front & rear seal & new tailshaft bushing & filter will suffice.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Not the best idea for a 30 year old transmission. The seals are old, the gaskets are dry, the valve body has been sitting for who knows how long (valves stick when they aren't being used). If you want the 'potentially' good tranny to live up to that 'potential', rebuild it properly and put a new torque converter on it. Or, just sell it to someone else who wants it and buy an already rebuilt 200R4 with lockup; that will give you good performance and decent economy.