Help driveshaft confusion!!!

[Kylejtucker]

Hello I have a 1997 gmc k1500 z71 offroad and I recently broke the aluminum/ carbon wrapped stock driveshaft. I went to the junkyard and pulled a steel drive shaft off of another gmc k1500 z71 offroad. My only problem is the caps for the u jiont on the steel driveshaft fell off and when I went to put the caps from the aluminum driveshaft on the steel one they are different sizes. So my big question it how do I know which u joint to get for this new steel driveshaft. The drive shaft does go into the trans and is the right length, i also pulled the yolk of the junkyard truck so I can swap those just need to know what u joint this is.

 

[delta_p]

You have to look it up, check the part numbers, go the part in the catalog for dimensions, and do some comparisons by measuring the cap or the bore in the yokes.

Drive lines are usually supplied to GM so the best places to look for parts is SKF, Spicer, etc. all of the drive line suppliers.

Check this start around page 128
https://www.skf.com/binary/79-66357/457285.pdf

Here is a spicer catalog. They don't list any for the C1500/K1500 but I used a spicer 5-795X on my '96 c1500 reg cab. very common part across many models.
https://www.macpek.com/wp-content/uploads/2014/06/Spicer-universal-joints.pdf

 

[454cid]

Here is a spicer catalog. They don't list any for the C1500/K1500 but I used a spicer 5-795X on my '96 c1500 reg cab. very common part across many models.
https://www.macpek.com/wp-content/uploads/2014/06/Spicer-universal-joints.pdf

I believe those aluminum/carbon-fiber drive shafts were Dana/Spicer. American-Axle/GM didn't ever make them that I'm aware of.

 

[deadbeat]

I believe the aluminum were a conversion and the steel were not. Seems they had different snap ring locations as well. I think the steel are a 3R dana.

 

[454cid]

I believe the aluminum were a conversion and the steel were not. Seems they had different snap ring locations as well. I think the steel are a 3R dana.

Conversion of what?

3R Dana? What are you trying to say?

 

[deadbeat]

The caps on the aluminum shafts were outside snap rings, the caps for all the 10 bolt rear ends were inside snap rings and 3R. I believe the aluminum caps were 1310 or 1330 sized, so a conversion was used at the rear with 1310 or 1330 caps one way, and 3R the other way.

 

[deadbeat]

This u joint is for steel front and back. All inside snap rings.

https://www.rockauto.com/en/moreinfo.php?pk=387875&cc=1051175\

This is joint is for aluminum front, all outside snap rings.
https://www.rockauto.com/en/moreinfo.php?pk=387727&cc=1051175&jsn=633

This is the aluminum rear, a conversion with inside snap one way and outside one way.
https://www.rockauto.com/en/moreinfo.php?pk=387729&cc=1051175

 

[454cid]

I wouldn't think GM would have used a conversion u-joint, but I don't have any experience with the Dana shafts. I wonder if the driveshaft has been replaced by a previous owner.

Those "inside snaprings" are to replace joints held in by injected plastic. You'll see tiny holes in the the flat spots that are ground into the side of the yoke ears on the driveshaft, and slip yoke.

 

[deadbeat]

The pinion didnt have injected plastic, and the caps had inside snap rings that the straps hold in. A conversion joint just means that 2 caps and distances between are not the same. Go pull one of the aluminum extended cab shafts and look, they have a conversion on the back. They have a different yoke on the front so a conversion is not needed. The front yoke on the steel ones has 3r both ways, the aluminum has 1310 or whatever it is.

 

[deadbeat]

I wouldn't think GM would have used a conversion u-joint, but I don't have any experience with the Dana shafts. I wonder if the driveshaft has been replaced by a previous owner.

Those "inside snaprings" are to replace joints held in by injected plastic. You'll see tiny holes in the the flat spots that are ground into the side of the yoke ears on the driveshaft, and slip yoke.

You are correct about the factory injected into the driveshaft, I heat these areas with a torch and the plastic melts out and looks like a pigtail.