Transmission stamp
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Instructor
Joined: Nov 2013
Posts: 249
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From: Piedmont Missouri
Transmission stamp
Could anybody help me out with this code stamped on my transmission? My car is a 69 and has a numbers matching motor, but it looks like this might not be the original transmission. I'm not sure what all the numbers mean. I think they read 28P318813 & P8E21. Thanks, Mark
Melting Slicks
Joined: May 2006
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From: Raleigh NC
St. Jude Donor '13-'14
Yours pre-dates the suffix coding (A for M20, B for M21, C for M22) but be sure it is not an M22 as Pontiac did not offer a combination with the M22 in 1968.
Pro
Joined: May 2012
Posts: 547
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From: Westminster Md
Hello Pete,
I have my transmission out of my 70 lt1 and i have the correct tranny but is does not have suffix code. How do i know what muncie i have?
Thanks,
Nelson007
I have my transmission out of my 70 lt1 and i have the correct tranny but is does not have suffix code. How do i know what muncie i have?
Thanks,
Nelson007
I cannot fault you for that assumption. Take solice in the fact that a Muncie is a Muncie is a Muncie. The gearing was the same for all GM Muncies.
Yours pre-dates the suffix coding (A for M20, B for M21, C for M22) but be sure it is not an M22 as Pontiac did not offer a combination with the M22 in 1968.
Yours pre-dates the suffix coding (A for M20, B for M21, C for M22) but be sure it is not an M22 as Pontiac did not offer a combination with the M22 in 1968.
Pro
Joined: Aug 2010
Posts: 698
Likes: 8
From: Stockholm Sweden
Pro
Joined: Aug 2010
Posts: 698
Likes: 8
From: Stockholm Sweden
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Melting Slicks
Joined: May 2006
Posts: 3,438
Likes: 41
From: Raleigh NC
St. Jude Donor '13-'14
Easiest method if it is out, count the rings on the input shaft. 2 rings = M20, 1 ring = M21, no rings = M22.
Pro
Joined: May 2012
Posts: 547
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From: Westminster Md