Does any one know whats the deal with the punch marks around the main bearing hole? is this a buba fix?
Muncie case ?
Racer
Joined: Sep 2009
Posts: 437
Likes: 3
From: Alvin Texas
A "buba" fix to tighten up the clutch gear bearing bore. The bearing has evidently failed at one time or the other and turned in the bore enlarging the bore to the point where the input bearing wouldn't seat properly. The penning was an attempt to "shrink a portion of the bore. Good idea to find another case, chances are the counter shaft bores are worn too.
Intermediate
Joined: Sep 2012
Posts: 35
Likes: 0
If you don't care about numbers matching, get an Autogear "Super Case". Many of the used cases out there are junk anyway, as they will leak oil around the countershaft pin in the front of the case. Muncies are famous for this. The super case solves this forever by being made thicker in that area, allowing for the installation of a soft welch type plug (included) in front of the countershaft pin. The case also has a drain plug installed, and they offer a heavy duty front bearing and iron midplate as well. All of the stock Muncie parts work with the super case. Check out www.autogear.net
Le Mans Master
Joined: Jan 2006
Posts: 6,504
Likes: 139
From: Butler Pa
If you don't care about numbers matching, get an Autogear "Super Case". Many of the used cases out there are junk anyway, as they will leak oil around the countershaft pin in the front of the case. Muncies are famous for this. The super case solves this forever by being made thicker in that area, allowing for the installation of a soft welch type plug (included) in front of the countershaft pin. The case also has a drain plug installed, and they offer a heavy duty front bearing and iron midplate as well. All of the stock Muncie parts work with the super case. Check out www.autogear.net
Rick, you mentioned "they will leak oil around the countershaft pin in the front of the case".
My m-20 leaks oil from the front of the case, but only when the car is in reverse and moving. No other time does it leak. Could my problem be the one you're speaking of?
Thread Starter
Intermediate
Joined: May 2012
Posts: 43
Likes: 0
From: Over The Hills And Far Away
If you don't care about numbers matching, get an Autogear "Super Case". Many of the used cases out there are junk anyway, as they will leak oil around the countershaft pin in the front of the case. Muncies are famous for this. The super case solves this forever by being made thicker in that area, allowing for the installation of a soft welch type plug (included) in front of the countershaft pin. The case also has a drain plug installed, and they offer a heavy duty front bearing and iron midplate as well. All of the stock Muncie parts work with the super case. Check out www.autogear.net
And speaking of the Super Case..is there a big advantage to changing to a Autogear tail shaft housing? And a steel mid plate is also on the menu.
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
If you're doing a super case, no more than the HD mid-plate costs I'd go ahead and do that too. And, if any of your sliders need replaced, get a set of the torque-lock type.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
I would be interested in hearing a response to this. Might start a new thread.
I don't mean to hijack this thread and I can start a new one if I need to.
Rick, you mentioned "they will leak oil around the countershaft pin in the front of the case".
My m-20 leaks oil from the front of the case, but only when the car is in reverse and moving. No other time does it leak. Could my problem be the one you're speaking of?
Rick, you mentioned "they will leak oil around the countershaft pin in the front of the case".
My m-20 leaks oil from the front of the case, but only when the car is in reverse and moving. No other time does it leak. Could my problem be the one you're speaking of?
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Intermediate
Joined: Sep 2012
Posts: 35
Likes: 0
I have been away for awhile. I purchased a restored 1936 Chrysler 5 window coupe. ( all stock). I now have a 720hp car and a 100 HP car. Trying to broaden my horizons, and all of that rubbish, LOL.
I am not sure about the tail housing. I built a Muncie using the Super Case, and I also incorporated their iron midplate because of the nominal extra cost, and the fact that many of the loads are against this plate as described on their web site.
Intermediate
Joined: Sep 2012
Posts: 35
Likes: 0
I don't mean to hijack this thread and I can start a new one if I need to.
Rick, you mentioned "they will leak oil around the countershaft pin in the front of the case".
My m-20 leaks oil from the front of the case, but only when the car is in reverse and moving. No other time does it leak. Could my problem be the one you're speaking of?
Rick, you mentioned "they will leak oil around the countershaft pin in the front of the case".
My m-20 leaks oil from the front of the case, but only when the car is in reverse and moving. No other time does it leak. Could my problem be the one you're speaking of?
All members interested in this subject should do a google search for "Muncie Transmission Leaks." You will be shocked at the amount of info that comes up on this subject. It is a very common problem with Muncies, and it is why Autogear invested the resources to solve the problem. You should not waste money on a used Muncie case unless you can accurately determine that the countershaft to case fit is correct, It must be a tight pressed -in fit. Disclaimer - I have no association with Autogear whatever, except for being a satisfied customer.
Last edited by Rick Rowland; Dec 11, 2012 at 11:23 PM.
Le Mans Master
Joined: Jan 2006
Posts: 6,504
Likes: 139
From: Butler Pa
Is the counter shaft the only place in front that can leak?
Like I said, it only leaks when in reverse and moving, and the leak is substantial. It's actually a small stream of oil.
The trans was rebuilt about 5 years ago and just started doing this last year.
I can't find anything referencing the transmission being in reverse when the leak occurs.
Like I said, it only leaks when in reverse and moving, and the leak is substantial. It's actually a small stream of oil.
The trans was rebuilt about 5 years ago and just started doing this last year.
I can't find anything referencing the transmission being in reverse when the leak occurs.
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
Seems as if the lube would slosh against the case any time he hit the brakes too.
But since nothing in the front of the trans turns backwards in reverse, I'm at a loss why it would only lrak in reverse. Any theories out there?
But since nothing in the front of the trans turns backwards in reverse, I'm at a loss why it would only lrak in reverse. Any theories out there?
Thread Starter
Intermediate
Joined: May 2012
Posts: 43
Likes: 0
From: Over The Hills And Far Away
Could it be leaking from the main shaft and oil "pooling" inside the bell housing..and when you backup it sloshes forward out of the bellhousing. When I removed mine the bellhousing had oil streek,and a stain where oil looks to sat for awhile.
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Its been my experience that there are STUPID people out there who are capable of beating the countershaft out the front of the main case on a rebuild. This will cause leakage in the case. Auto gear super case has a seal on the countershaft. No leaks. I use weatherstrip adhesive in my stock rebuilds on the countershaft. Before driving it all the way home coat ID of bore at the front with WS adhesive. Be sure the countershaft is properly rotated before WS adhesive has set up by installing mid plate before WS adhesive has set up. DONE!
Intermediate
Joined: Sep 2012
Posts: 35
Likes: 0
Case in the photo is JUNK! Get another. I have several in my spares pile if you want original otherwise go Auto Gear.
Its been my experience that there are STUPID people out there who are capable of beating the countershaft out the front of the main case on a rebuild. This will cause leakage in the case. Auto gear super case has a seal on the countershaft. No leaks. I use weatherstrip adhesive in my stock rebuilds on the countershaft. Before driving it all the way home coat ID of bore at the front with WS adhesive. Be sure the countershaft is properly rotated before WS adhesive has set up by installing mid plate before WS adhesive has set up. DONE!
Its been my experience that there are STUPID people out there who are capable of beating the countershaft out the front of the main case on a rebuild. This will cause leakage in the case. Auto gear super case has a seal on the countershaft. No leaks. I use weatherstrip adhesive in my stock rebuilds on the countershaft. Before driving it all the way home coat ID of bore at the front with WS adhesive. Be sure the countershaft is properly rotated before WS adhesive has set up by installing mid plate before WS adhesive has set up. DONE!