theandies

I finally got my rear end out and the cover off. I was very surprised that it looked so good in there...almost brand new. There was no visible metal in the oil and both "c" clips are intact. My question is what is the acceptable endplay for the yokes? I searched the archives and really didn't see a definitive answer. I have not measured the endplay yet but both yokes have some. One side is a little worse than the other and I estimate it to be about 1/8 to 1/4 inch. The other side is less. Second question. Other that a total rebuild how is the endplay reduced? The end of my yokes look great too.... no mushrooming what so ever.
Thanks

Big Fish

.050". Play is caused from wear on the ends against the cross shaft. Play is corrected by replacing the yokes and possibly the cross shaft as well if it's worn.

45ACP

I've never found an "official" figure for the endplay for C2's and 3's, but found one for C4's: between .0005"and .0085"

This seemed reasonable to me for my rearend also.

Using hard facing rod, I very carefully welded up the ends. I then ground down the weld until I achieved .0005" clearance.

I should mention that I am a machinist and have access to the proper equipment to get this done. If you aren't a machinist (or don't know one) don't have a go at this. This is not a fix for the typical hobbyist.

GTR1999

If the rear end was stillin the car and you had .040-.060" I'd say leave it alone. Since you have the rear end out change the yokes now. Some of the original yokes were not hardened too good in the mid 70's and wear quickly. For $65 you should be able to get rebuilt yokes with hardened tips. Look at the posi center pin(shaft) you'll see some wear marks but these are harder then the yoke ends so it shouldn't be too bad. The pins are still available from GM for about $25 if you need one.
If you plan on removing the carrier mark the bearing caps first you don't want to mix them up. rotate the carrier and look for any cracks between the "windows" and the center pin hole. Look for signs of the yokes hitting the housing and signs of oil leaks.
Gary

theandies

Thanks
I'll take some pictures and let you guys be the judge. Can the center pin be replaced easily? I will probably get the hardened yokes just so I don't have to do this again in the near future. I inspected the carrier good and didn't see any cracks or other defects. There are no oil leaks on any of the seals. The case just needs to be cleaned up and painted. I am now in the budget stage of the rear end project and just trying to get an idea of what I need.

GTR1999

The pin can be replaced without removing the carrier unless you have a 4 series with 411 or 456 gears then the ring gear will be in the way. With the yokes out rotate the pinion until you see the 7/16 hex head bolt in the carrier. This bolt is long and goes into the pin to secure it. Remove the bolt and internal star washer and the pin will slid out. You have to position the carrier to remove the pin but it's not hard to do.
Good luck let me know if I can help,
Gary

theandies

Awesome and thanks Gary. I'll let you know if I need some additional help. I am going to change the side yokes and the pin and be done with it. I'll keep you posted.
John

edit - Oh BTW the gears ar 3.36's so I should be able to get the pin out.


[Modified by theandies, 11:24 AM 6/23/2004]

theandies

I measured my endplay.
Right = .0460"
Left = .0256"
I took the right side out and it looks to be just starting to mushroom a bit. Everything else looks great. Pictures came out blurry so I'll have to shoot some more later.

My thinking is leave the left side alone and get a rebuilt hardened right one.
Any pitfalls besides having to do the right in the future? I am doing a complete trailing arm/rear suspension rebuild so that should relieve a little stress on the yokes with new bushings/4-wheel alignment. This is just a street Vette with an occasional 1/4 mile blast (3 times in 4 years that I've owned it).

Big Fish

If it were mine, I don't think I would have any problem whatsoever leaving the better side in. You could still see a lot of miles from that part. The other side is right to the limit though.

GTR1999

You can get by with the .025" side but I would still replace it with a harden tip one. For $65-$70 it's worth it to know both sides are done-but it's your money. Good luck,
Gary

mrvette

You know, it's entirely possible the side gear is recessed into the carrier a bit on account of worn posi clutches....that allows the end play to go to the outside without any wear on the yokes being visible....if the clutches are not really badly worn, maybe a shim is in order.....but that all is not very critical anyway compared to the yoke/crosshaft wear patterns.....early sharks had pretty hard yokes, and do not fail nearly as often as later sharks....

GENE

SWCDuke

There is no side yoke end play spec, but a properly set up new positraction case with proper one to six thou differential gear backlash and yokes with no end wear should be no more than ten thou.

As the clutch pack and yoke ends wear, end play increases. Yoke end wear appears to be more prevalent on C3s than C2s.

Duke

Duke