‘83 K5 NP208/Corp 10 bolt- Front Driveshaft U-joint PN/size?

[BlazerBill]

I had a shop install the u-joints into the front and rear driveshafts for my ‘83 K5. When I attempted to install and tighten the front driveshaft u-joint clamps, the bearing is too small and slides out of the clamps and the length (end cap to end cap) of the u-joint is too short. The
u-joint bearing cap OD measures 1.06” on all 4 bearing caps and fits in the driveshaft yoke side with the retaining clips but is too small for the clamps to tighten down. Are there two different sizes on this u-joint? I found one of the old bearing caps and it measured 1.120ish”. Does anyone know the part number for this front driveshaft u-joint, the dimensions of it and where I can buy it? See pics. Thanks, all!

 

[legopnuematic]

It looks as the pinion yoke is an internal clip style, what does it measure from inside ear to inside ear?

I’d guess you need a 1310 to 3R conversion u-joint.

 

[idahovette]

After spending your hard earned dollars, I would be sure and go back to the shop and pitch a bitch!!!!!!

 

[BlazerBill]

Inside ear to inside ear 2.340. See pic. Assuming that’s the measurement your asking about.

 

[legopnuematic]

That measurement, but on the pinion yoke (differential). That is the measurement that internal clip joints use, like a 3R the old Detroit style u joints, etc.

A 3R joint is 1.125 diameter caps and 2.5625 ear to ear.

 

[BlazerBill]

Pinion yoke ID. 2.56” confirmed and 1.125” Clamp ID confirmed. Is the 1310 to GM 3R u-joint correct from Denny’s Driveshaft website? See pics

 

[BlazerBill]

What does the 3R mean?

 

[legopnuematic]

That Neapco joint should work fine.

The 3R is what that size is referred to as, like a 1310, 1410, 7290 don’t know why.

 

[BlazerBill]

Thank you, so much for the quick help!!!! I’ll order it.

 

[Old Guy Bill]

Aren't 3R are those evil bastards that have the plastic injected, and no clips?
That's what my '78 GM 10 bolt had originally.