grp

I've read the archives for this project and they make it sound easy (basically drop the driveshaft, pull the old one out and put the new one in). However, I put the car up on blocks and starting looking around last night. To me it looks like there is a bracket/brace right where the trans/drive shaft meet. Does this need to be moved for this? A related question is how do I know if the 4spd is a Muncie? Is there a stamp on it?
Thanks folks

Koz

The bracket/brace should be the rear trans support that goes from one side of the car to the other. That does not have to be removed.. Just remove the universal strap bolts and drop the drive shaft.. The yolk should then pull out.
Get yourself a seal puller for $10 and thank yourself afterwards for doing so.. :yesnod:
I thought you would have the same tranny as mine but the production code for your car is M21 and mine is MM4 (Borg Warner). I believe I read in another thread that the yolk doesn't slide out of the Muncie's.. Hopefully someone else will chime in.. Good luck!


[Modified by Koz, 4:30 PM 7/9/2003]

Fevre

Mine slid right out, hope that is not a bad thing. :eek: I did notice some wear but I am going the 5 speed route so I just sanded smooth and jammed it back in. With the new seal it does not appear to be leaking like it did prior to seal replacement.

grp

Thanks for the confirmation guys. Guess I will rollup the sleeves and give it a shot. Question for KOZ - how did you know my Trans is a Muncie?

Koz

I don't know that's why I hoped someone else would chime in. The specs on a '78 said it was an M21 4 speed manual close ratio.. My year was a MM4 4 speed manual and I have the Borg Warner. Since the codes were different and the descriptions were different I couldn't be sure. Just wanted you to be aware that IF you have a Muncie I believe the yolk doesn't just slide out. Again I thought I read that in another thread.. If you have the Borg Warner then your all set..

Just saw that Fevre has a '78 with the slide out yolk.. You should be fine..

Fevre, Do you have a Borg Warner or a Muncie in your '78?


[Modified by Koz, 4:59 PM 7/9/2003]


[Modified by Koz, 5:00 PM 7/9/2003]

grp

just curious. thanks again for helping out.

Fevre

'73, not sure if it was diff for later years or diff Muncies, mine is a m22.

GTR1999

I believe Muncie were dropped in '74 and ST-10 used in the 75 and up?
Look at the side cover bolt pattern- they're different. Some repair manuals show the difference, I also think Muncie have 7 bolts and the ST-10 have more?
The yokes pull out of the Muncies once you get the driveshaft out of the way.
Gary

nitrocharger

I believe the Muncies have a rounded shifter plate on the side and the BW's were square. Make sure you check to rear bushing as well. A worn bushing will cause the seal to leak. I had to replace my seal twice because of this. :thumbs:

grp

Okay guys. I have the drive shaft down and the seal pulled out. I assumed I had the Muncie so that is the replacement I bought. The "housing" part of the seal I bought was roughly twice the depth of the original. Sure enough there is a ridge on the tranny side so I couldn't get the seal to go in. I noticed the letters W.G. Mfg. stamped on the housing. Guess I don't have a muncie after all. Will head back to the auto parts store tomorrow with the original in hand to be sure this time. Thanks again to all. Also, if anyone knows how I can tell exactly what Trans I have please advise.

JK78SA

Depending upon which engine you have (assuming it is original) will dictate what tranny you have. In 1978 the L48's got the Saginaw wide ratio tranny.
The L82 standard 4 speed was a Borg-Warner wide ratio & a Borg-Warner Close ratio was optional. The Saginaw has a 7 bolt cover & the Borg-Warner's have a 9 bolt cover.

Several months ago, I pulled my Saginaw out (didn't like the gearing after my engine rebuild) & replaced it with a rebuilt Muncie (from an early 70's Corvette)- I like the gearing in it much better. I really preferred replacing with a Borg-Warner wide ratio, but then I would have had to replace my clutch, pressure plate, flywheel, etc.

I am not sure if Muncie & Saginaw tranny's use any common parts, ie. rear seal.

You may find this website to be helpfull in identifying which tranny you have. http://www.dandltransmission.com




[Modified by JK78SA, 11:27 PM 7/9/2003]

grp

JK78SA - much help, thanks. I have the L82 - 4spd so must be a Borg-Warner if original. I will check for the 9 bolts. Also have the seal in hand so I can compare it at the parts store. Thanks again.

fauxrs

Your L-82 will have the Borg-warner. Muncie slip yokes do slip out of the transmission just like every other manual transmission I have ever seen in a GM product. I have worked on Opel 3 speeds, Saginaw 4 spds, Muncies 4 speeds and Borgwarner ST-10's and every one of them has a slip yoke.

Rich's78$pit

Fauxrs,
Do you know what the maximum safe torque handling capability of the Saginaw is? I have a 78 L48 355 rebuilt to about 350 ft lbs torque and I am wondering if it will stand up to another 50 ft lbs I hope to gain with aftermarket heads (stock heads with 3 angle, gasket matched to Edelbrock intake, 222/222 cam @.05", headers, 2.5" dual exhaust, 3.36 rear gears). I do some hard launches but never "dump" the clutch.

fauxrs

The saginaw is a weak transmission, especially when attached to a V8, it was use donly in low horsepower V8 applications, v6's and 4 cyls. However it is more a function of driving style, its shocks to the tranny that cause most damage, if you arent speed shifting or dumping at launch it will probably last OK. I would say however that you are quite aways beyond the recommended torque capacity of that transmission, which I am sure is no more than 300# lbs.

Find yourself a good BW St-10 - its about 30# lighter and stronger by a significant amount.


[Modified by fauxrs, 12:00 PM 7/10/2003]

Rich's78$pit

Fauxrs,
Thanks for the reply. I didn't mention that I did have it rebuilt by a good tranny shop that does other Vette trannies in this area, so I hope it will hold up. You reinforced my thinking that if I want more power I need to price a tranny along with heads. I thought I would be happy with what I had, but now I want more power! (I should have known!).

Fevre

Check out summit, they have a beefed up SuperT10 for about $1,400.

http://store.summitracing.com/produc...earchtype=ecat