U joint blow out & repair on custom driveshaft PROJECT COMPLETE

[Preston]

Ok here we go again, my 85 Silverado just picked it up from the shop around the corner A/C leaked down (bad Schneider valve) no problem. The shop is just far enough for me to get my foot into it and go through the gears and then there’s a light for me to turn, what happened as the transmission went to shift into high gear something came apart I immediately pulled over to the side of the road truck now idling oil pressure good temp normal no knocking I got out looked nothing leaking driveshaft still hooked up nothing dangling. So I slowly headed home 1/4 mi I felt a slight vibration in the steering wheel oil pressure great temp gauge okay no weird noises anyway it’s 95 degrees I parked under a tree and checked under the hood again all belts ok no smoke ,no fire and no leaks gonna go and check it out when it cools down. I just changed the flex plate will look at torque converter and leaks just thought I would post this will update ASAP just unusual to have a wheel shimmy after a loud noise all wheels are rolling nothing wobbling.

 

[Preston]

Problem found rear universal joint, crapped out on me. Maybe I didn’t torque it down after replacing the flex plate. I’m so glad it’s not the transmission.

 

[Preston]

Okay, the rear universal joint has inside clips and I remember they were very tight going in, other than using a micrometers how do I know I’ll buy the right one. This is a custom cut aluminum shaft aren’t most universal joints the same on each I’m wondering if all 1985 rear “U” joints are the same ? May need a little help, or just take the old broken one and figure it out, I didn’t get 1,000 miles out of this one could have been defective. What I’m trying to say I may need a “U” joint with different widths by a millimeter the end that goes in the driveshaft is wider than the one going in the rear.

 

[Preston]

Okay I’m slow but I figured it out, take the yoke off the rear and the driveshaft to my parts store or speed shop and get the right one.

 

[Preston]

But, all I need is one cup for my rear “U” joint it’s a Spicer SPR 539. I didn’t drive the truck enough to damage anything, I can file the end of the u joint to fix it but I can’t find the cup it must be in orbit somewhere or could be stuck under the bed somewhere. I know these joints come with extra cups for the inside c clips or outside spring clips, would I be setting up for another breakdown if I used the cup for the spring clip without the clip on this setup? I’m having trouble finding a new “U” joint the drive shaft has outer clips and the rear has inner c clips I went to the local auto shops and they can’t find the SPR 539 if anyone can tell me if the other cups are interchangeable or should I just get a new one. This is a custom driveshaft that originally came out of a Ford pickup need to be more than 6’ couldn’t find one from a gm vehicle that long. Thanks for the help.

 

[4WDKC]

But, all I need is one cup for my rear “U” joint it’s a Spicer SPR 539. I didn’t drive the truck enough to damage anything, I can file the end of the u joint to fix it but I can’t find the cup it must be in orbit somewhere or could be stuck under the bed somewhere. I know these joints come with extra cups for the inside c clips or outside spring clips, would I be setting up for another breakdown if I used the cup for the spring clip without the clip on this setup?

double check the cap is fitting right in the yokes.. Same thing happened to my friends car with me driving 30-40 mph cruising slow loud thunk and vibration, stop the car identify the caps missing, moved to parking lot. He ordered a new drive shaft for his Turbo LS Mailbu with 8.5" diff. they sent him the wrong u joint and he didnt notice it. The caps working loose damaged the yoke on the diff. The company sent the correct ujoint and split the cost of a billet yoke with him. Luckily it happened while going slow and not one of the 100mph blast he had been doing.

 

[Preston]

I found a couple needle bearings in the end of the cap, that would be enough to make the c clip not fit. I have drive the truck for 100 miles or so lucky I was close to home when it broke thanks for the help I need all I can get.

 

[4WDKC]

I found a couple needle bearings in the end of the cap, that would be enough to make the c clip not fit. I have drive the truck for 100 miles or so lucky I was close to home when it broke thanks for the help I need all I can get.

he had also put some miles on his when the caps came off, his came out because the caps were just small enough to not be tight with the straps ran all the way down but big enough to look like they were correctly installed.. I walked the road after we moved the car and found one of the caps while he was calling a tow truck.

 

[Preston]

What was the solution bigger “U” joint caps or smaller straps?

 

[4WDKC]

What was the solution bigger “U” joint caps or smaller straps?

New ujoint with correct size caps and new yoke since the original was damaged.

 

[Preston]

Thanks

 

[Preston]

I’m having trouble finding this u joint

You must be registered for see images attach

 

[4WDKC]

thats a number on the cap not necessarily for the ujoint itself.

 

[Preston]

No that’s the center of the u joint

 

[Craig 85]

It looks like 539 is a Spicer casting number. Look at the bottom of the link.

https://www.northerndrivetrain.com/product/SPI-5-1330X.html


I found this for a Ford only application.

https://fortwayneclutch.com/product...-cap-ford-series-universal-joint-sku-5-7438x/