MYBAD79

Yesterday I tried to get these U-joints out but because it's an aluminum driveshaft I did not want to press too much... I used a big C-clamp and a little heat, U-joint did not move at all...
I did not have any problems when I did the U-joints on the Corvette (used same method, C-clamp and sockets)

.... didn't see any clips holding the cup in place ...wtf ????

Edit:
just did my 'homework' and searched the www for more info on these U-joints. It seems GM used a nylon pin to secure them in the driveshaft. This pin has to be melted, then the Ujoint can be pressed out.
Well.... my new U-joints came with new clips, no new nylon pin. Oh well.... the old U-joints are still good... I'll leave the new ones on my shelf until the old ones go bad.....

pws69

Aren't there clips on the INSIDE of the cups (toward the center of the UJoint) ?

MYBAD79

Only on the rear Ujoint I found two clips on the inside. That's on the two cups that are bolted to the differential yoke.

The front U-joint is pressed into the driveshaft and the tranny yoke, no bolts, no clips....

I guess I'll take some photos tonight.... I'm not worried about the Ujoints falling out, this is how it's been for the past 90K miles and it doesn't look like the U-joints were ever replaced. I just want to find out what's holding them in place....

BTW, this is on a '99 Z28 (at least a Chevy)

gkull

I use a 10 ton H-Press to R&R U-Joints in my Half shafts. You just have to jig it up good so nothing gets bent.

pws69

I still find it hard to believe that there are no clips. Last U-Joints I did were in my '98 Tahoe (sometimes I miss that thing!) and there were clips in them, but hard to dig out.

MYBAD79

I added to my first post.... I wonder who had the brilliant idea to use nylon pins to secure U-joints....

... well.... to answer my own question; GM ....nylon pins are cheaper than metal clips If they could they would have used a Velcro strip...

68 NJConv 454

Hummm I hope the velcro string doesn't unravel and get twirled up in my trany yoke...I'm sure I'll find that bubba installed the aftermarket GM velcro straps on my driveshaft, he couldn't do anything else right... why start there!! bastad!!!

JJGoodwrench

The nylon pins you're talking about aren't really pins. What you are looking at is the hole/s that the manufacturer injects liquified nylon. The inner circumference of the u-joint socket on the yolk has a groove in it and the cap has one that corresponds with it. When the nylon is injected it hardens and the joint is solid. To get it out without bending the yolk, you heat the yolk (I use a propane torch so I don't melt the aluminum) and when it gets hot enough it will squiggle out. Just make sure you wear goggles as I have seen this stuff pop out with enough force to really sting and it's hot! Then you would remove the joint with your C clamp or U-joint tool. The replacement joints will have clips to hold them in. Internal or external.
JJ