More fun with numbers

[mcditalia]

Being that my car has been on ramps for the past month tooling around with the heater and other things, I looked a little better at my trans. I was very surprised to find an identification tag on one of the left side bolt where it should be. 3870354 corresponds to the M20 wide-ratio trans. I did a little digging and was trying to see if the L79 only came with the close-ratio M21 or available with the M20 or M21. I got conflicting answers, so which is it?

On the right side I also got P1111, which I'm assuming is the assembly code and stands for Nov. 11th and the P is for Muncie 4 speed. My motor assembly date is Nov. 16th, kinda cutting it close between the two, no?

Lastly, I was trying to find the vin derivative stamping which should also be on the left side but where? I can't seem to find it, but I should say I wasn't really looking for that long. thanks.

 

[ZRGator]

I can't answer your tranny questions (I'm sure one of the pro's in here will) but the stamping you are looking for is on a boss in front of the right side
(left side if you're standing in front looking in) valve cover.

 

[JohnZ]

3870354 corresponds to the M20 wide-ratio trans. I did a little digging and was trying to see if the L79 only came with the close-ratio M21 or available with the M20 or M21. I got conflicting answers, so which is it?.

The '66 L-79 could be ordered with either the M20 or M21.

 

[stepinwolf]

Lastly, I was trying to find the vin derivative stamping which should also be on the left side but where? I can't seem to find it, but I should say I wasn't really looking for that long. thanks.

If memory serves me correctly, you should find the vin stamped vertically, on the left side at the rear of the main case, You should find it near a slight flange , where the main case meets the tail section. The main case is rather porous, and if it's not sparkling clean, or the stamping is on the light side, it becomes very difficult to see.

In the past I have found that if you hold a trouble light up close and at a slight angle, the shading makes the numbers easier to read.

Stepinwolf

 

[ZRGator]

Aw, jeez, rereading his post, I see that he was referring to the VIN stamping on the tranny and I thought he meant the engine stamping...durrrr.:eyerole