‘79 K20 Camper Special U-joints
 

Replacing my rear driveshaft with a better one with no slip yoke wear, swapping the u joints first. I always have trouble looking up parts for this truck because of the weird combination of parts. 10 bolt front, NP203/TH400 with a 14FF rear axle. The Rockauto Autozone, whatever references are almost always wrong. I pulled the old ones off, likely the originals. The transfer case end says Spicer P621. I believe the new Spicer # is 5-760X. Its not greasable, I wouldn’t mind having one that is. The axle end u joint is larger, caps 1-3/8” approximately. One side says “Spicer Can” with numbers F3-5-69 and a big X in the middle. The other side says A525. None of these numbers are helpful when trying to look it up. I’m hoping the 14FF used a standard u joint and somebody here knows the part number.

Re: ‘79 K20 Camper Special U-joints
 

It most likely has 1310 U-joints with a 1350 at the rear axle.

Re: ‘79 K20 Camper Special U-joints
 

Take your cup dia. and overall width to the chart.
https://neapcoaftermarket.com/wp-con...og-9901018.pdf
G numbers are non greasable.

Re: ‘79 K20 Camper Special U-joints
 

That’s a great chart, and Al guessed right. Thanks both for your help.

Re: ‘79 K20 Camper Special U-joints
 

Should have 5-760x on the rear shaft 1350 series (both joints)

Re: ‘79 K20 Camper Special U-joints
 

I actually moved my slip yoke to behind the transfer case and used a conversion U joint at the rear axle. Now the slip yoke has a much calmer life than it did bouncing around and twisting with the rear axle.