Differential issue...

[| 1990 ZR-1 |]

Originally Posted by lbszr

I still would want to verify play in the yoke before tearing into it. Did you check with the wheel on at the 12 and 6 position, with the spring connected to the knuckle it might be hard to move and it might take another person to watch the yoke.

If you still don't feel any play, could try disconnecting the spring from that knuckle and try again, if you haven't already.

Not for this rearend, but gm 12 and 10 bolt, I've bought parts from http://www.drivetrainspecialists.com/

I could not get any play at the yoke at all. The car is already jacked up with the wheel removed so I'll disconnect the spring tonight and see if there is any play in the yoke. I'll let you know.


On a side note, I thought that Dana 44's and the ZR1 drive trains in general are bullit proof. I don't drag race the car or drop the clutch of the lights, only some spirited dirivng on the weekends. It only has 34k miles, adn the only mods are headers, high flow cats with cat abck exhaust, and SLP intake. At the same time, I've only had the car for about 7 months, and don't know much if it's history. I think the extra weight i was hauling and the worn out bushings strained the suspenssion compenents too much and allowed the drive shaft push into the diff and damage somethign in there. Just a word of causion I guess.


Does anyone have a write up on step by step diff removal? I'll also check in our tech section.

[lbszr]

Originally Posted by | 1990 ZR-1 |

I could not get any play at the yoke at all. The car is already jacked up with the wheel removed so I'll disconnect the spring tonight and see if there is any play in the yoke. I'll let you know.


On a side note, I thought that Dana 44's and the ZR1 drive trains in general are bullit proof. I don't drag race the car or drop the clutch of the lights, only some spirited dirivng on the weekends. It only has 34k miles, adn the only mods are headers, high flow cats with cat abck exhaust, and SLP intake. At the same time, I've only had the car for about 7 months, and don't know much if it's history. I think the extra weight i was hauling and the worn out bushings strained the suspenssion compenents too much and allowed the drive shaft push into the diff and damage somethign in there. Just a word of causion I guess.


Does anyone have a write up on step by step diff removal? I'll also check in our tech section.

With the wheel removed, it's hard to get the leverage needed to find play.

If you still don't feel the play, it's a tough call, the yoke rubbing into the housing would probably cause me to tear it apart anyway. But it would be a lot of work. I do remember a write up of somebody taking theres out and doing all the bushings on this site.

[| 1990 ZR-1 |]

I was finally able to pull the diff out this weekend and take it apart. Sure enough one of the side yokes is worn out all the way to the C clip. I'm having a real hard time finding those side yokes for sale any where. Do you guys have any suggestions?

Also, does anyone know what would cause only one of the side yokes to wear? I'm planning to repalace the side berrings and seals, everything else seems to be okay.

[Ccmano]

Originally Posted by | 1990 ZR-1 |

I was finally able to pull the diff out this weekend and take it apart. Sure enough one of the side yokes is worn out all the way to the C clip. I'm having a real hard time finding those side yokes for sale any where. Do you guys have any suggestions?

Also, does anyone know what would cause only one of the side yokes to wear? I'm planning to repalace the side berrings and seals, everything else seems to be okay.

Can you take a photo of this and post it? This still sounds really weird. How does the old bearing look?
H

[a1991zr1]

There is no way in h$ll you damaged the Diff. Take your car down to the local firestone as they tend to have the best alinement machines out there, and get the alignment checked. I would say 95% chance the rear camber got knocked out. I have had way more than 300 lbs in the back of mine and never had an issue. you can check this yourself with a barnyard alignment the service manual give you all the measurements take two levels and hold them on the outside of each rim and measure the distance from the level right to left front of tire and rear of tire and let me know what you get.

[lbszr]

Originally Posted by | 1990 ZR-1 |

I was finally able to pull the diff out this weekend and take it apart. Sure enough one of the side yokes is worn out all the way to the C clip. I'm having a real hard time finding those side yokes for sale any where. Do you guys have any suggestions?

Also, does anyone know what would cause only one of the side yokes to wear? I'm planning to repalace the side berrings and seals, everything else seems to be okay.

Does that mean there is not much of a groove left for the C clip to be in?

How much metal from the end of yoke shaft appears to be gone, compared to the other side?

Does the inward end of the yoke push against the pinion shaft surface, and also the wear point? Just making sure I understand where it is worn.

I doubt if a heavy load or anything you did caused this. A one wheel burn out for a really long time is the only way I can think to really cause friction on the end of the yoke. Maybe a loose yoke bearing could set up some kind of movement causing wear. Maybe the yoke was just inferior with a soft spot on the end. The end play might of been set up wrong, there is suppose to be 8 different thickness C clips for adjustment. Sorry just thinking out loud.

http://www.drivetrainspecialists.com/categories/dana/ Might have something. Corvette Central, or White Racing. Guess you already tried the dealer?

[Jagdpanzer]

Try Tom's Differentials, catalog page 32
http://www.tomsdifferentials.com/catalog.asp?pg=32

or Ikerds
http://www.ikerds.com/catalog/group13/group13.html

Please post a photos so we can get a better idea of your problem.

[| 1990 ZR-1 |]

Thanks for all the replies gents. I'll try to answer all questions from today, and provide more info. Please bear with me since it's my first time opening and seeing inside of a diff. Also here are some pics. Please note that C clip is already removed at the time of taking the pictures.

After removing the diff and before even opening the cover, the driver side yoke had an approximate 1/4" in and out movement, while the passenger side yoke did not have any play at all, as it should not. After removing the cover, the problem was apparent. The inner part of the driver side yoke that butts against the spider gear cross shaft is worn out by about 3/16th of an inch, just enough where the C clip was almost resting against the cross shaft. You can see from the pictures that yoke is worn. I guess I lucked out that C clip did not fall off the yoke and cause more damage. Now this could have been an ongoing issue that maybe even started before I got the car. The side bearing does have a little bit of play in it, but I’m no expert. I will replace both side bearings and seals as a precaution. I believe that the worn out bushings in the spindle rods along with the extra weight in the trunk and me going over a dip at a higher speed than I should have with the extra weight somehow put too much strain on yoke or the bearing or both and caused this issue. I'm going to replace the yoke and the bearings and I think I should be okay. Please tell me if I'm missing something here. Thanks!

[a1991zr1]

good catch at least it is not to costly as a repair. Glad to see you figured it out

[Ccmano]

Looks like bearing failure, faulty installation or side impact on the wheel caused the yoke to push in against the pinion shaft. I would also inspect the bearing seat in the case for damage. I'm thinking accident damage somewhere in the past that was not picked up. (or ignored)
H