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#46900 06/27/2005 1:09 AM | Joined: May 2005 Posts: 3 Junior Member | | Junior Member Joined: May 2005 Posts: 3 | Hello, I'm having some difficulty in deciphering my transmission codes. The tranmission is from a 1964 fleetside truck with an original 292 inline six, and is a 4-speed manual. The code, located above the transmission cover, reads:
C174
GM
3837334
Now using the "car and parts catalog of chevy truck id numbers '46-'72" the letter 'C' means powerglide build in cleveland, obviously not correct. Now, this is supposed to be a 4-speed munchie from what I was told, and comparing this transmission to orignal pictures in the factory assembly manual, it looks *exacty* like the one in the assembly manual. I am almost 100% certain it is the orignal transmission, all but this code leads me to this conclusion.
In the factory assembly manual, it shows in the 1964 Transmission section that a "type C" transmission is a M23 type (a munchie 4 speed), but dosen't say where this "C" would be, maybe this is my answer. If anyone could be of any help I would be grateful, maybe it wasn't stamped exactly like it should have been, or maybe is not what I think. Thanks... | | |
#46901 06/27/2005 1:33 AM | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | the " 'C' means powerglide build in cleveland" has to do w/ the vehicle VIN number, not the part number - if the trans is most likely original and looks like the one in the manual, and the manual sez it's a M23 ....... what was the question?  the C174 might mean M23, but I'd expect it's more likely a date code like march 17, 1964? not sure how they were dated, but they were - the 383 number is the trans case casting number, and they were all stamped exactly as they 'should have been', even if not quite legible at times Bill | | |
#46902 06/27/2005 1:43 AM | Joined: Dec 2004 Posts: 452 Member | | Member Joined: Dec 2004 Posts: 452 | The C174 would be the casting date code, and not the transmission ID code. March 17, 1964 would be correct for that. 3837334 is one of the casting numbers for the case of an SM420. The serial (ID) number would be stamped (not cast) on the rear of the case, toward the right side, just below the top edge (above output shaft). The Muncie 4-speed ID number should begin with an N.
Curt
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1953 Chevy 6400, 1957 Chevy 2dr Sedan
--"Mediocrity is easy, the good things take time"
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#46903 07/05/2005 1:49 AM | Joined: May 2005 Posts: 3 Junior Member | | Junior Member Joined: May 2005 Posts: 3 | Thanks for the input guys. Curt, thanks you got it, the transmission is covered in sludge so I didn't see that back number, I'll check it out soon (trans is not here at the moment), but thanks for clearing up my confusion!
Joe | | |
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