Jag rear end play

[DanEC]

Bob/others - I noticed that there is a little play in the rear suspension when pulling on the tire at the 6 and 12 o'clock positions (jacked up with suspension at full droop). Jerry rigging a dial indicator to bear on the outside of the rim at the top of the wheel - I get about 70 to 80 thousands of movement rocking the wheel. I haven't played around with it enough to tell if it's axial movement in the half shaft, bearing rock in the outer carrier or a combination of the two. Does that sound pretty much normal?

Thanks

Dan

[ERA Chas]

Same test procedure; mine had about .125.

[DanEC]

Originally Posted by ERA Chas

Same test procedure; mine had about .125.

OK - good. I'm used to a lot of play in my 66 Corvette rear suspension because of the C-clip retainers in the differential - just wasn't sure about Jag stuff. Thanks Chas

[PeteF]

Mine has similar play at 45,000 miles. I did not measure the amount, but I can feel it and hear it when moving the tire up and down. I can see it move in the outer hub carrier, the inner joint in the diff is not loose at all. I seem to remember a limit for outer hub/bearing looseness in the Jag manual, but do not remember the number. Mine has not degraded in 6 years, so I just check it during my Spring maintenance. Also, to feel better, I once turned the engine off while coasting down a long grade to listen for any bearing noises. No growling or unusual noises, so I keep driving. I expect someone will chime in soon with a limit.

[DanEC]

I think mine is in the hub carrier also. I enlisted the wife to yank around on the tire while I tried to look underneath and that's what it looked like - but I couldn't be sure. I know on mid-year Corvettes, the lower suspension link and little bit of negative camber keep the axle loaded against the differential gears in just about all conditions with the exception of leaving the ground all together. I suspect the Jag suspension is much the same.

[mickmate]

Have someone wiggle it for you while you look underneath. I just replaced inner stub axle bearings in a Jag diff that did that. The new bearings are sealed cartridge style and very nice. That's likely what ERA uses but it would be nice to see where it is coming from as it might be all from one place. I don't think it's unusual between inner and outer axles and inner and outer u-joints to have a stack up of tolerances resulting in what you are feeling. The half shafts are the upper arms in the suspension so you don't want to see, feel or hear excessive play. They do a pretty good job of letting you know when they are ready to be changed.

[ERA Chas]

My play was at the outer hub. Stubs had no slack. Also no noise. Kept the zerks full each year however.

[RICK LAKE]

Dan Ec Need to isolate the play heres the 3 possible things
You said the play is top to bottom
Start with hub bearing, are yours geaseable or presealed units? Grease them and see if play is less or about the same.
Less you need to repack the bearings in the hub assembly
Same is another location for the movement

If the same start to work inward. First place would be to grease the lower control arm bushings on the hub and control arm. Grease them until it comes out and recheck. No play would replace lower bushings and shafts.

Same play would be to see if the right spacer for the drive shaft to the hub is correct. Doug setup my end plays for this and have .005" and .009" on the play with the correct bearing torque.

last check would be the location around the rotor assembly and see if play can be seen The stub shaft bearings could be worn out and have side to side play. You would also have a brake problem with vibration when stopping or noise. Look to see if both pads are the same thickness on the rotor.

Check the bushings or bearings on the lower control arm where it bolts to the cradle again grease and recheck.

I would think it's the end play of the drive shaft between shaft and hub bearing. You didn't say how many miles are on the car and spirit driving you are doing.

I went 3 miles and blew out the r/r hub bearing for being too tight with the spacer. I learned my failure and when back to ERA and Doug. setup took worked perfect. have had no failures in the last 15 years.

Close eye and touch 1 piece at a time for movement, you will feel it when you get the right spot. Good luck Rick L.

[joyridin']

I had mine rebuilt about 4 years ago by the now defunct CWI. They do have play top to bottom and at the outside of the wheel, .100" sounds about right. I think it was .03" at the hub.

Mine is a pretty old style set-up, so I am not sure if that is a factor or not.

[DanEC]

This car doesn't quite have 100 miles on it's ERA assembly yet, so I'm comfortable it's not worn parts - although a defective part is always a possibility. I just wanted to get a feel for what is normal so I can keep an eye on it.

Thanks

[kevins2]

Hi Dan,

The play you describe is normal. You may recall I posted a video on my thread of a bearing problem I had with the Jag rear. With someone moving the wheel at the 12 and 6 position, you could clearly see the inboard brake rotor wobble, indicating it was a defective bearing on the inside where the half shaft mounts to the diff, so that would be what you want to look at when looking under the car with someone moving the wheel. ERA replaced the bearing and that solved the problem.

Kevin

[DanEC]

Originally Posted by kevins2

Hi Dan,

The play you describe is normal. You may recall I posted a video on my thread of a bearing problem I had with the Jag rear. With someone moving the wheel at the 12 and 6 position, you could clearly see the inboard brake rotor wobble, indicating it was a defective bearing on the inside where the half shaft mounts to the diff, so that would be what you want to look at when looking under the car with someone moving the wheel. ERA replaced the bearing and that solved the problem.

Kevin

Kevin - I remember your bearing issue but I can't seem to find the thread where you posted the video. Was it in your build thread?

Thanks

[kevins2]

Hi Dan,

Yes, below is a link to that page. The video link is toward the bottom of post #104. You can clearly see the excessive wheel wiggle and the brake rotor moving. There is also a photo of the bearing that had to be replaced. From what you described, the play you have is in the hub and is normal. But it wouldn't hurt to have someone wiggle the wheel and watch the rotor just to make sure.

First Pics of ERA #795

Kevin

[DanEC]

Originally Posted by kevins2

Hi Dan,

Yes, below is a link to that page. The video link is toward the bottom of post #104. You can clearly see the excessive wheel wiggle and the brake rotor moving. There is also a photo of the bearing that had to be replaced. From what you described, the play you have is in the hub and is normal. But it wouldn't hurt to have someone wiggle the wheel and watch the rotor just to make sure.

First Pics of ERA #795

Kevin

Thanks Kevin. I overlooked the video.

I think you are right. I didn't notice any movement like that at the brake rotor.