4-speed Transmission Tag Question

[Mark A.]

Hi,
My 71 Lt-1 Has A Metal Tag On The Side Cover That Is Stamped 3981710wy. Underneath On The Main Case Is A Stamping From A Rubber Pad That Says Wy. The Number Does Not Correspond With The Vin#. Does Anyone Know What The Number Is, And What Wy Means? Thanks, Mark

[Lynn H.]

Re: 4-speed Transmission Tag Question

Any chance you could post some photos?
Lynn

[Mark A.]

Re: 4-speed Transmission Tag Question

I'll see what I can do. Mark

[Mark A.]

Re: 4-speed Transmission Tag Question

Here is picture of tag and maincase. The ink stamped WY went underneath the tag on the lower part of maincase. It was removed during the rebuild process. Mark
[ATTACHDSC01037.jpg]21651[/ATTACH]

DSC01036.jpgDSC01037.jpg

I have attached the pics, but I'm not sure if I did it right. If you can't open it, I will have to talk to somebody to see how to attach the photos.

[Edward J.]

Re: 4-speed Transmission Tag Question

Mark, the tag your looking at is a part no. tag from GM.

[Bill C.]

Re: 4-speed Transmission Tag Question

Mark,

My car has a M20 and my tag ends with WD.
The ink WD was stamped on the bottom of my car too - but lost it when doing the restoration.
Maybe WY is for a M21..

I have wanted to reproduce it, but have forgotten the size/font.

Could you post a picture of your ink stamp?

[Edward J.]

Re: 4-speed Transmission Tag Question

Bill Did'nt The Suffix Code Stamped On The Trans. A,b,c Designates The Transmisson Type M20,21,22

[Bill C.]

Re: 4-speed Transmission Tag Question

Ed,

I believe that is correct.

The tag is a whole different thing - It is pt# tag as stated above.

You are speaking of the VIN stamp on the side of the case.

[Joe L.]

Re: 4-speed Transmission Tag Question

Here is picture of tag and maincase. The ink stamped WY went underneath the tag on the lower part of maincase. It was removed during the rebuild process. Mark
[ATTACH[ATTACH]21651[/ATTACH]]21651[/ATTACH]

[ATTACH]21652[/ATTACH][ATTACH]21651[/ATTACH]

I have attached the pics, but I'm not sure if I did it right. If you can't open it, I will have to talk to somebody to see how to attach the photos.

Mark------


GM #3981710 is the part number, PRODUCTION and SERVICE, for the 1971 close ratio Muncie transmission. "WY" is the broadcast code for that transmission.

If the transmission has the car's VIN derivative stamped on it, then it's original to the car. If it has some other car's VIN derivative, then it was originally installed in another 1971. If it has no VIN derivative stamping, at all, then it's a SERVICE transmission, but of the correct part number for a 1971 with close ratio trans.

[Mark A.]

Re: 4-speed Transmission Tag Question

Bill,
I don't have it stamped yet. What I did was take my maincase to a print shop when I dissassembled the tranny. They were able to match up the font and size perfectly on a rubber stamp pad. Mark

[John H.]

Re: 4-speed Transmission Tag Question

Bill Did'nt The Suffix Code Stamped On The Trans. A,b,c Designates The Transmisson Type M20,21,22

Ed -

Yes, but that's a suffix to the Muncie "P"-code (assembly date) stamped on the passenger side near the rear of the main case.

[Warren F.]

Re: 4-speed Transmission Tag Question

I believe on that metal tag the two letter suffix at the end of the part no. is like an ECL code for the type of transmission. Both of my '71's have WO for an M22.

[John H.]

Re: 4-speed Transmission Tag Question

I believe on that metal tag the two letter suffix at the end of the part no. is like an ECL code for the type of transmission. Both of my '71's have WO for an M22.

Warren -

That's the "broadcast code" - if you have the build manifest sheet, you'll find that code in the box labeled "Trans"; that's how the guy on the line selected the correct transmission to pick out of the shipping rack.