The Stovebolt Site Forums The Shop Area Engine Shop 4 SPEED TRANS SWAP

I'm considering an upgrade to a 4 speed man. trans in my 57 chevy stepside. It currently has a 3 speed man. on the floor and I was wondering if anyone has any experience with trannie swaps other than early muncie and saginaw and could pass on some words of wisdom. I have a 350 cu chev motor and a 12 bolt chev rear w/3:73 gearing. I'm looking for something fairly straight forward, nothing too radical as far as fabrication. Thanks for your help!

The 58 i'm working on has a 4 speed Saginaw. It was in when I got it but it's a straight forward swap. The Saginaw or Muncie fit right in. You will probably have to modify the drive shaft & the hole in the floor for the shifter. I got a new shifter from Hurst as the one on it was sloppy. The Muncie is a stouter trans. but either one will work unlessyou are going drag raceing.

I would look at a NV3550 from the S-10's or a ZF from the 88-93 pickups myself to go with a 5-speed.

Sorry. I misread read it. It says any thing other then a Saginaw or Muncie. Scott is right, a 5 speed would be better with 3.73 gears.

I'ld go with a Borg Warner T5 out of a chevy S10. Smooth shifter and overdrive. The T5 can take torque up to 300 Ft Lb. Pretty straight forward check the Stovebolt tech pages, theres a couple of detailed project on the tranny swap. Also allot of stuff on the internet about the tranny swap to a T5. Be careful and don't get schnookered like I did and buy a Borg Warner T50. I put a T50 (sold tome as a T5) in my 46 the first go around. I learned a good lesson though. If the casting number on the tranny is not 13-52, it's not a T5. If the casting unmber is 13-38, it's a T50 (LOSER TRANNY). Take a look at the T% I think you'll like it

Only the Camaro and Cobra T5's can take 300 lb-ft. The S-10's are limited to 220.

Jimbo, nothing wrong with a T50 other than the 3+2 shift pattern. That transmission was behind everything that GM made in the mid 70's including the 260 and 305 V8's I ran one for years behind a hyperactive Buick 3.8 putting out 330hp.

Scott.

Scott can you explain the 3+2 shift pattern. I'm not sure what that means. I own a Corvette with a 4+3 and wonder if it means something similiar.

The T50 has the same R, 1, 2, 3 shift pattern as an old 3-speed with two extra gears of 4, and 5. Unlike the traditional 4-speed and 5-speed. It makes first to second gear shifts a bit odd. It was refered to as 3+2 by those that were not enamored with the shift pattern.

The T-50 has a
shift pattern of:

R 2 4
1 3 5

The T5 is a later, stronger, and much more popular transmission, with variants
being used by Ford, GM, and Chrysler. The T-5 shift pattern is:

1 3 5
2 4 R

(taken from the following)

http://thewedgeshop.21.forumer.com/a/which-5-speed_post198.html

http://www.britishv8.org/Articles/Borg-Warner-T50-Transmission.htm

The T50 is not recommended for anything with greater than 110 Hp. I would not use the T50 if, for the same money you can get a T5.

Get a New Process Trans.,used by GM. GM called the trans. MY6.
The trans. is three speed,fourth being overdrive.

Direct replacement for the saganaw.

If you use a MY6 trans. Be sure to get the shifter and shift rods.

Jimmy

Jimmy,
The MY6 sounds like the ideal trans for my application. I'd like to do the T-5 with an overdrive but I think that may be farther down the road right now. Are these expensive units and are there a lot of them around?