Muncie Transmission Tag and ID

[Paul C.]

What does the tag 3981710WY and stamp C11S102461 indicate on a Muncie M21 ?

[Warren F.]

Re: Muncie Transmission Tag and ID

Paul,

The metal tag gives you the part # and Broadcast code for your close ratio manual transmission. The stamping is the 1971 VIN derivative for your Corvette which is an early model 1971, car number 02461.

[Paul C.]

Re: Muncie Transmission Tag and ID

The date code however is P1P01B which is late in the year.

[John C.]

Re: Muncie Transmission Tag and ID

Paul

Transmissions dates were stamped with the model year they went into and not the year of production. Your date of P01 is for Sept. 1 of 1970. Perfect for and early build car.

John

[Paul C.]

Re: Muncie Transmission Tag and ID

Thank you. What does the WY indicate ? Does that correspond to the engine or rear ratio ?

[David L.]

Re: Muncie Transmission Tag and ID

Paul,

The "WY" is a code for the 3981710 transmission that was stenciled on the top of the transmission in large letters for easy identification on the assembly line. This 2-letter code is also shown on the build sheet.

My 1971 Chevrolet parts catalog lists GM # 3981710 as a 4-speed transmission as follows: "71* ALL w/Muncie close ratio" in Gr. 4.003. The asterisk (*) signifies exclusively new for the 1971 model year.

In the photo below box # "28 TRANS" of this 70 Camaro SS350 body build sheet has the letters "WB". The tag on the transmission is stamped "3952659 WB".

Dave

[David L.]

Re: Muncie Transmission Tag and ID

Enclosed is a photo of a 4-speed Muncie transmission with a large "WB" stenciled on the top (1970 Camaro SS350).
The tag is "3952659 WB".