MUNCIE METAL TAGS

**427king** · #1 04-13-2008, 06:32 AM

Can anyone tell me where i can find nfo for decoding metal 4 speed tags for muncie m20 21 and 22. I have 40 or 50 of those metal tags from mostly 69 and 1970 and would like to decipher some of them.

**Lynn** · #2 04-13-2008, 06:58 AM

3950356 is for RPO M20 with L48, L34, L35, LM1
3946797 is for RPO M20 with Z28 & L78
3946798 is for RPO M21 with Z28 and L78
3950318 is for RPO m22 with Z28 and L78

I believe this info is according to the AIM for 1969 models.

Lynn

**427king** · #3 04-13-2008, 06:59 AM

Thanks ...Any info on decoding the 2 letter codes [ie WO for 70 chevelle m22 etc that are at the end of the part #] ?

**Lynn** · #4 04-13-2008, 07:06 AM

Don't know about 70's, but I bet someone here does.

**mockingbird812** · #5 04-13-2008, 07:08 AM

Mr70 knows this stuff. Hey Rick!

**427king** · #6 04-13-2008, 07:11 AM

actually im looking for that 2 letter code and part #s info for 69 as well as 70...

**Mr70** · #7 04-13-2008, 07:17 AM

Lots of people contributed,but credit goes to Chuck Hanson for publishing this all in last months Chevelle World.Box #28 on the Buildsheet will reflect the 2 letter code as well.
Muncie ID Tags
1964 M20 3841435
1965 M20 3857577
1965 M20 3857578 Z16
1966 M20 3870357 L-34 L-35
1966 M20 3890534 L-78
1966 M21 3877459 ALL
1966 M22 3879993 L-78
1967 M20 3870357 L-34 L-35 L-79
1967 M21 3877459 ALL
1967 M22 3879993 L-78
1968 M20 3915079 L-34 L-36 L-78 L-79
1968 M21 3915085 L-34 L-36 L-78 L-79
1968 M22 3925626 L-78
1969 M20 3950301 L-48 L-35
1969 M20 3946767 L-34 L-78
1969 M21 3946798 ALL
1969 M22 3950318 L-78 COPO L72
1970 M20 3952659 WB
1970 M21 3968012 (disc.3-11-70)
1970 M21 3968011 WL
1970 M22 3978766 WO
1971 M20 3974484 WN
1971 M22 3978766 WO
1972 M20 3974484 WN
1972 M22 6271517 WJ

**Igosplut** · #8 02-18-2013, 11:51 PM

I have a dog food can full of these, perhaps I should check them...

**Lynn** · #9 02-19-2013, 03:21 AM

All the four speeds in 69 got the hurst shifter.

I believe the answer to the question was submitted by crash: "Different speedo gears on the main shaft..." Crash

The Z and L78 would likely have the lower rear axle dictating different speedo gears to at least get close on the speedo.

**mockingbird812** · #10 08-20-2013, 07:56 PM

I noticed above that "3950316 is for RPO M21 with L34" but I have the same tag on an M21 for a low mile L78 (4.10 rear) car. Would that be possible?

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