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TH400 swap to M20 4 speed


domac444
10-20-2008, 04:40 AM
I want to swap my TH400 for a muncie 4 speed. I know I will have to change the slip yoke to a 27 spline output but do I have to change my drive shaft and/or crossmember?

MrPbody
10-20-2008, 09:33 AM
Driveshaft, yes, cross-member, no.

The driveshaft will be about 4" too short.A driveshaft from a car equipped with TH350 or PowerGlide should be the correct length. The cross-member slides forward, and the mounting holes should already be drilled in the frame. You may need a different cable for the parking brake, too.

Jim

bobss396
10-20-2008, 12:14 PM
I hate to step on anyone's toes, but the TH400 comes in two lengths. One is the same length as the TH350, Powerglide, Muncie and Saginaw (3 & 4 speed).

The other is longer and came in some trucks and station wagons only. I can wander out to the garage and measure one up if you need to know the long TH400 length is.

Bob

MrPbody
10-20-2008, 01:27 PM
Bobn,

No toes... You're right in that TH400 came in two lengths. The SHORT one is 4" longer than the normal TH350, and ALL the PowerGlides. A limited number of cars got a "long tail" TH350. The "long tail" 400 is really a TH375. It's a light duty version used in full-size cars.

Jim

bobss396
10-20-2008, 05:01 PM
Cool, the long tailed trannys usually came in the wagons from what I saw of them. I swapped lots of things back and forth, the only time I ran into problems was when I needed a TH400 yoke, otherwise I can't recall many problems.

Bob

domac444
10-21-2008, 10:08 AM
Bob
I'm a little confused as to which t-400 I might have, short or long tail shaft.
I measured mine and it is 35 inches long. Which tranny might I have??
Carl

bobss396
10-21-2008, 11:48 AM
I have the long one at home, I'll have to go and measure it up and get back here with the number. Try to Google it and you may come up with some pix to help you. Once you see the two next to each other the difference is obvious at the tail of the housing.

Bob

MrPbody
10-21-2008, 01:09 PM
The main portion of the case is the same between the two. If the tail "cone" is about 4" long, you have the "short tail". If it's over 8", long tail... (:-

Jim

domac444
10-21-2008, 06:59 PM
I have the long tail shaft housing (9''). Looks like I'll be shopping for a longer drive shaft. Thanks for all the help.

Carl

MrPbody
10-22-2008, 08:29 AM
Carl,

Where are you located? Depending on where you are, I may be able to recommend a driveshaft shop. Your best bet is to find the local driveshaft "guru" (a real shop, not a backyard deal) and have a new one made. You will be surpirsed at the price, as driveshafts aren't REAL expensive unless you want something odd.

Jim

bobolink24
10-22-2008, 08:38 AM
Sorry to break in like this with a new topic, but it seems almost impossible to start a new thread on this board.
My problem is: I want to put a camaro/nova front clip under my "56 Chev pu. Anyone have any how-to smarts on this kind of project? Is there any 'conversion kits' on the market? Or is this going to be a "get out the torch and get started" type of project? Thanks

72chevelleOhio
11-03-2008, 02:00 AM
Cool, two threads...:tongue:
Sorry to break in like this with a new topic, but it seems almost impossible to start a new thread on this board.
My problem is: I want to put a camaro/nova front clip under my "56 Chev pu. Anyone have any how-to smarts on this kind of project? Is there any 'conversion kits' on the market? Or is this going to be a "get out the torch and get started" type of project? Thanks
Click this (http://www.automotiveforums.com/vbulletin/forumdisplay.php?f=1938)
then click "new thread" on the left side middle of the screen.
put in your title and then write what your looking to do in the big box.

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