Is this the original prop shaft?

[Hans R.]

1. I have dis-assembled the propeller shaft on my 66 Coupe #6634. Both end yokes has a p/n 3742995 marking. Is this the p/n for the yokes and not for the shaft assembly? Is this an original prop shaft?
2, Both yokes are marked with a bow tie and one has a number 251H and the other 252H. Anyone knows what these numbers mean? See pictures.
3. I have had my differential restored. Is there any specific way I should allign all the yokes (at transmission, at differential and at the wheels) when I put it all together again?
Appreciate your help on this. Hans Ryden #868

[Joe R.]

Re: Is this the original prop shaft?

Hans,

Boy, nobody is stepping up to this one.

I'll take a shot in the dark.

The part number is for the yoke and the other number represents the mold number and the mold cavity.

Casting companies did not cast either aluminum parts or cast iron parts individually. There was a mold with several cavities. They were identified for convenience to the operator. When something was wrong with the casting they could identify the mold and mold cavity that was giving them trouble. If it happened to be a sand casting the bets are off.

Hey, not a bad shot for an old guy!

JR

[John H.]

Re: Is this the original prop shaft?

Hans -

If the driveshaft is still in one piece (yokes welded to the tube), just install it as is. If the yokes have been cut off the tube and the tube is being replaced, weld them on parallel with each other (phased the same way), and have the assembly balanced (including the front slip yoke).

There's no phasing for the half-shaft yokes and U-joints; just assemble everything and go - the phasing will change the first time you turn a corner.

Ignore the note in the Chassis Service Manual that says to phase the differential side yokes 90 degrees from each other - that's a well-known misprint (see paragraph above).

[David L.]

Re: Is this the original prop shaft?

The 1963-early 1970 Corvette driveshafts are GM #3830618 (Gr. 5.441 and later changed to Gr. 5.544). The length is 29.90" (center to center u-jt caps). The overall length is 31.78". The tube thickness is 0.095" and the tube diameter is 2.00".

The late 70 driveshaft (GM # 3963852) is the same as above except the tube thickness is 0.120".

The driveshaft part number does NOT appear on the driveshaft