1972 LT-1 Drive Shaft Finish and Part Number

[Michael B.]

I removed the badly rusted drive shaft from my 72 LT-1 for u-joint replacement. After soaking the shaft in Evapo-Rust for a few days I discovered a portion of the part number. The first four number were 3921, the next number looked like it may be an 8, and the remaining numbers were gone. Quanta said the number should be 3921675. Anyone know for sure?

Secondly, the surface of the driveshaft looks exactly like the half shafts with that textured appearance. Researching previous posts indicates the shaft should have been smooth steel and not the shot peened appearance. Again, anyone know for sure?

Thanks.

Mike

[Joe L.]

Re: 1972 LT-1 Drive Shaft Finish and Part Number

I removed the badly rusted drive shaft from my 72 LT-1 for u-joint replacement. After soaking the shaft in Evapo-Rust for a few days I discovered a portion of the part number. The first four number were 3921, the next number looked like it may be an 8, and the remaining numbers were gone. Quanta said the number should be 3921675. Anyone know for sure?

Secondly, the surface of the driveshaft looks exactly like the half shafts with that textured appearance. Researching previous posts indicates the shaft should have been smooth steel and not the shot peened appearance. Again, anyone know for sure?

Thanks.

Mike

Mike------


3921675 was the original part number for the driveshaft. This part number was never available in SERVICE since it included the u-joints. SERVICE driveshafts did not include the u-joints. The SERVICE driveshaft was GM #3924148.

The 3921675 was used for all 1972 Corvette applications and was not shot-peened.

[Michael B.]

Re: 1972 LT-1 Drive Shaft Finish and Part Number

Thanks Joe. I was hoping you would see my post as I know you have the answer to questions like this.

I guess the texture I'm seeing on the shaft is due to rust pitting and not shot peening.


Mike

[Joe L.]

Re: 1972 LT-1 Drive Shaft Finish and Part Number

Thanks Joe. I was hoping you would see my post as I know you have the answer to questions like this.

I guess the texture I'm seeing on the shaft is due to rust pitting and not shot peening.


Mike

Mike-------


These driveshafts were just natural steel finish. In a non-severe rust environment (e.g. California and south western states) they rust. In a severe rust environment (e.g. New England and mid-western states), they rust BADLY.

If yours has significant corrosion pitting I recommend going with a new shaft.

[Erich M.]

Re: 1972 LT-1 Drive Shaft Finish and Part Number

Mike,

Attached are 2 pictures of my driveshaft. PN 3921675 IS CORRECT FOR AN ORIGINAL SHAFT.

ERICH MEYER
72 LT1 BOWTIE, TOP FLIGHT
ORIGINAL OWNER008.jpg009.jpg

[Michael B.]

Re: 1972 LT-1 Drive Shaft Finish and Part Number

Thanks Eric and Joe.

Mike