Drive shaft ujoint questions

[Steve Addy]

Hey all, been a while...

I don't see a specific section where this belongs...the sections here are kind of confusing IMO, there seems to be no place for people with stock trucks. Anyway, I'm having trouble locating correct part number info for new ujoints for the C3500 6.5TD truck so I'll drop this here and see what I get...

I have a vibration that's driving me nuts so the driveshaft has been taken off and gone to the shop to be checked. The rear most ujoint seemed notchy but ok, but since it was already off it would be good practice to replace them all anyway. Besides, none of the originals are greasable and I like to be able to service ujoints etc.

This is a 4x2 reg cab LB truck with the 2 piece driveshaft, 4L80E trans and JB8 brakes on the 14 bolt rear FF axle.

The two rear joints look to be the same and I can check at the yoke with a slide caliper to find the extreme measure, so that's ok, but I would still like to see original GM part number for all these just to be sure.

At the trans however, the ujoint is smaller, but that's not reflected in the online parts houses anywhere. They all just say it's the same joint for everything OR they conveniently only have information for the joints on the rear shaft.

Anyone have any info or a good source that I can refer to?

Thanks

Steve A

 

[Schurkey]

1. "The shop" you took the shaft to should be able to figure out what replacement U-joints you need.

2. The rearmost U-joint is the most-common one to fail.

3. If a U-joint is "notchy", it's not "OK", it's JUNK.

4. Sealed-for-life, non-greasable U-joints are the strongest. There's no need to grease them.

5. If you want GM part numbers, go to a GM dealership and ask them. Bring your VIN number.