Standard u-joint replacement help

[BigOrange90Jimmy]

I have an '86 K10, and I'm replacing the u-joint on the rear driveshaft at the transfer case. The joint I'm replacing is the original, so I've heated it to melt the plastic retainer that GM used. The problem I'm having is finding a replacement. The joint that Advance calls for is entirely too large.

The measurements that I've taken are as follows:

Inside yoke-to-yoke - 2 9/16"
Cap diameter - 1 1/8"
Internal lock style

By those measurements, it's telling me I have a S44 or GM 3RL u-joint. Am I right and their computers are wrong? The joint size they come up with is a Moog 534G, which is entirely too large.

 

[diesel4me]

Maybe this will help..http://www.actionmachineinc.com/ujointmeasuringguide.aspx


http://www.driveshaftspecialist.com/HTML Measure/UJ ID Guide.html



I'd guess your assumption is correct...it's common for the listings to be wrong or maybe something was swapped somewhere along its life..when I was a parts counterman,it was a pain getting the "right" u-joints for a customer--even if the vehicle was 100% un-molested,the listings were often not correct..then you had to get the calipers out and use the size chart in the back of the catalog..

 

[Deuling]

You should have a 3R joint from what i have heard.

 

[thearborbarber]

You are both right.

http://www.summitracing.com/parts/MOG-534G/

I wonder if the wrong joint was put in the right box. I've had that happen recently with brake pads.

 

[diesel4me]

You are both right.

http://www.summitracing.com/parts/MOG-534G/

I wonder if the wrong joint was put in the right box. I've had that happen recently with brake pads.

Highly possible--often when I sold U-joints and the customer wasn't sure which one of several that were listed actually fit their truck,they would simply buy one of ALL the possibilities,and return the ones that didn't fit...

Unfortunately they often got put back in the wrong boxes,or the caps from one joint ended up on another one,and it caused a lot of hassles for the next person who came in to buy one!..

We had to do a forensic investigation every time one was returned,in hopes of preventing that from happening,but many of the other counterworkers just shoved the box back on the shelf,without looking over what was in it good...and I was usually the lucky one to sell it to someone,only to have them come back fuming saying "you gave me the WRONG ONE!"....
I started measuring any that had been removed from the shrink wrapping to avoid that dilema..

 

[BigOrange90Jimmy]

I went to Advance last night and was able to go to their u-joint section behind the counter, where I proceeded to open every last box of joints they had in stock. I'm pretty sure the one I needed was in the two sections they were sold out of. Regardless, of those that their computer "said" would fit, all were too large. I did manage to source it at NAPA this morning with a counter guy that knew how to use a catalog.

 

[thearborbarber]

What was the NAPA part number for future reference?

 

[BigOrange90Jimmy]

Interestingly enough, Napa's part number for the joint was similar to Advance Auto's: PUJ 534G