Question on transmission main case casting number

[Justin S.]

Would someone be able to tell me the applications for GM #3915032?

Thanks,
Justin

[Gary B.]

Re: Question on transmission main case casting number

Justin,

I found this via a Google search:

RPO Years Casting 1st 2nd 3rd 4th Spline (Input) Pin Spline
-----------------------------------------------------------------------
Saginaw
M20 67 3915032 3.11 2.20 1.47 1.00 L6 engine
M20 67 3915032 2.54 1.80 1.44 1.00 V8 engine

Gary

[Mark F.]

Re: Question on transmission main case casting number

Would someone be able to tell me the applications for GM #3915032? Thanks, Justin

Justin,

The Camaro Research Group says it's for a '67 Camaro...dunno if there were more applications or not.
My bet is Joe Lucia would know.

...The 1967 Camaro main case casting number is 3915032, the extension housing is 3860042, the side cover is 3890527 and the front bearing retainer is 3859033. Note that the 6 cylinder Saginaw 4 speed transmission casting numbers are the same as the V8 Saginaw 4 speed transmission casting numbers. Only the "guts" are different....

http://www.camaros.org/forum/index.php?topic=17376.0

[Justin S.]

Re: Question on transmission main case casting number

Thank you Gary and Mark.

[Joe L.]

Re: Question on transmission main case casting number

Justin,

The Camaro Research Group says it's for a '67 Camaro...dunno if there were more applications or not.
My bet is Joe Lucia would know.

...The 1967 Camaro main case casting number is 3915032, the extension housing is 3860042, the side cover is 3890527 and the front bearing retainer is 3859033. Note that the 6 cylinder Saginaw 4 speed transmission casting numbers are the same as the V8 Saginaw 4 speed transmission casting numbers. Only the "guts" are different....

http://www.camaros.org/forum/index.php?topic=17376.0

Mark------


Yes, the GM casting number 3915032 was used for the cast iron main case of 1967 model year Saginaw 4 speed transmissions. These transmissions were used in lower performance applications for the 1967 model year. These included Camaros as well as other Chevrolet models. NONE were used for any 1967 Corvette. For 1968 and and later, the casting number for these transmissions changed to 3925656. These were also used for lower performance 4 speed applications for many Chevrolet models but never Corvette. They were used through 1975 and, possibly, later.

By the later 70's the manufacture of the old Saginaw transmission was transferred to the Muncie transmission plant with the original Muncie 4 speed ceasing PRODUCTION after 1974. The Saginaw transmission became a "Muncie" and MAY HAVE changed to an aluminum main case, although not the same as the original Muncie. These transmissions were used in lower performance 4 speed GM applications in the late 1970's and possibly early 1980's. These included 1978 Corvettes with L-48 and some early 1979 Corvettes with L-48. The casting numbers for the main case of these transmissions was GM #3925656, the same as the earlier Saginaw 4 speed.

The 3925656 main case, GM part #3925654, was discontinued without supercession in January, 1993.

[Justin S.]

Re: Question on transmission main case casting number

Thanks a lot, Joe.

[Mark F.]

Re: Question on transmission main case casting number

Mark------


Yes, the GM casting number 3915032 was used for the cast iron main case of 1967 model year Saginaw 4 speed transmissions. These transmissions were used in lower performance applications for the 1967 model year. These included Camaros as well as other Chevrolet models. NONE were used for any 1967 Corvette. For 1968 and and later, the casting number for these transmissions changed to 3925656. These were also used for lower performance 4 speed applications for many Chevrolet models but never Corvette. They were used through 1975 and, possibly, later.

By the later 70's the manufacture of the old Saginaw transmission was transferred to the Muncie transmission plant with the original Muncie 4 speed ceasing PRODUCTION after 1974. The Saginaw transmission became a "Muncie" and MAY HAVE changed to an aluminum main case, although not the same as the original Muncie. These transmissions were used in lower performance 4 speed GM applications in the late 1970's and possibly early 1980's. These included 1978 Corvettes with L-48 and some early 1979 Corvettes with L-48. The casting numbers for the main case of these transmissions was GM #3925656, the same as the earlier Saginaw 4 speed.

The 3925656 main case, GM part #3925654, was discontinued without supercession in January, 1993.

Joe,

Thanks much...I knew you'd know the whole story...

If you ever get time to write a book on all the stuff you know, lemme know 'cause I'll gladly buy it !

[Mark E.]

Re: Question on transmission main case casting number

Joe,

Thanks much...I knew you'd know the whole story...

If you ever get time to write a book on all the stuff you know, lemme know 'cause I'll gladly buy it !

This forum is the book, but better because it has a search function.