Decoding a 02D 1969 Z/28 Transmission P9B18(O)

[TooManyReels]

I can't make out the last letter on my transmission. I would like other opinions as to if the stamping make this an M20 M21 or M22. The stamp looks like an O instead of and open C...The last letter is up against the radius of the transmission and very hard to see if there is a break in the letter ...It's not clear even when I take a picture of it.. Its surely not and A or B, so I'm assuming it to be an M22...Your thoughts or opinion...


TMR
Eddie

[william]

A '69 M-22 would have a drain plug.

[bertfam]

Post a picture with the lighting at a 45 degree angle to the transmission. That might help.

Ed

[TooManyReels]

I will try and load some pictures tomorrow...The transmission does have a drain plug half way up the passenger side in about center of the main transmission housing.

TMR
Eddie

[william]

That's the fill plug. M-22 drain plug is at the bottom. Other Muncies have provision for it but it is not drilled & tapped.

[TooManyReels]

HUM!!!! Then the best guess would be an M21....Since no lower tapped drain plug...

TMR
Eddie

[TooManyReels]

Here are the two best photo's that I took..



Let me know what you think the last letter is...

TMR
Eddie

[IZRSSS]

...Let's try this again...assuming the last letter is "D" (must be because there are not any O's in the decode table).

http://www.camaros.org/drivetrain.shtml#trans

P=   4-speed Muncie
9=   1969
B=   Feb
18= 18th day of the month
D=   Day shift

My guess M21...
 

[TooManyReels]

I thought the last letter was to tell the type A= M=20, B=M21 and C=M22...Is this not correct...
I'm thinking M-21 as well....
Eddie

[IZRSSS]

Eddie,

The last letter is the suffix...you could be correct if the last letter is a C...& I guess that is possible. If this is true then you have the M22. It can't be an O, & it certainly does not look like an A or B...I believe it's a D. Remember, you don't have the drain plug Bill mentioned so the M22 is slim to none.

s  = suffix
       PowerGlide and TH350 (not used on all):
          D = day shift
          N = night shift
       1969 Muncie 3-speed
          B = 2.42 first gear ratio
       1969 Muncie 4-speed only:
          A = M20
          B = M21     Use of the Muncie type suffix
          C = M22     began with 21 Oct 68 production

[tmodel66]

Snatch the side cover off and see if it's a M22. The gears have a different pitch and you can tell right away. I take it you didn't check it out when you restored or bought the car?

[TooManyReels]

I did inquire as to what type of transmission it was, but the person that owned and restored the car never checked or seemed to care...I'm going with the M-21 since I don't want to remove the side cover...

Thanks for the help...

Eddie

[68Zproject]

It's easy to tell when you drive it.  When you start out and it seems like you might have it in second gear or third but it is in first, then it's an m21 or m22.  Then, if you can hear yourself think without the shift boot on, it's an m21.

[bcmiller]

The D and N suffix was only used for PowerGlide and TH350.  Never used for Muncies.

You are going to have to post some better pics if we are going to figure this out.