I am trying to eliminate a pronounced vibration in my MY95 XJ6. I have narrowed down the problem to either the driveshaft balance or the diff. I'm thinking (and hoping) the balance is probably the culprit but I'm having a devil of a time finding a shop that can balance the shaft. No one in the area seems to have an adaptor to handle the the jurid coupler.

Anyone know of a place that can do it in NC?

If not, anywhere else? I'd hate to ship it but will do so if I have to.

Cheers,

Allan

 

I am not sure about the coupler, but I have always taken my automobile drive shafts to tractor trailer repair shops for balancing. Maybe they can help you.

 

Weren't you gonna intall a monostrut in hopes of fixing the vibration? Am I remembering correctly?

Anyhow....


I wonder if removing the coupler would be an idea?

What make you think it's a driveshaft problem, just out of curiosity?

Cheers
DD

 

Hi Doug,

Yes I did indeed install the monostrut but that did not cure the problem. I'll make a separate post on the X300 forum when I have found a solution, it's one of those "thigh bone is connected to the knee bone" things

The vibration starts at 30mph, very pronounced. Then lessens but is still felt at higher speeds. Originally I thought the problem was the donut as it had many visible cracks. Also the center support bearing rubber had collapsed. Replaced them both along with the u-joints and did a driveshaft alignment as per the VSM. A slight improvement but the problem was still there.

Then I spotted that one of the upper pendulum bushings had failed. So it was down with the rear end and sure enough there was no rubber between the inner and outer metal of the bushing. At this time I also noticed that one of the dogbone struts had misformed ends so I changed those to the monostrut and replaced all the bushings in the rear end. Also the diff was leaking at the output shafts so replaced the seals and bearings as well.

Put everything back and still the same problem. Disconnected the axle shafts from the diff and ran the car on stands, problem still there. Disconnected the driveshaft from the tranny, you guessed it, problem gone.

So my thoughts are driveshaft balance or diff. I did measure the diff pinion runout and it was right on the limit (0.003"). Don't really fancy rebuilding the diff so I want to start by eliminating the driveshaft from the equation.

 

Also I think removing the couple would present it's own set of problems as I'm sure it's not perfectly balanced to start with and there is very slight clearance in the bolt holes all of which would definitely throw the whole balance off.

Good news though, thanks to Arthur at V12 Motorsports in Charlotte, I did find a place that has the necessary equipment to do the job. Hopefully that will solve my problem

 

Good sluething :-). I know there's a lot of labor involved in what you've done.

As you may recall I've been battling a vibration problem as well. Well, sort of. I attack it in fit and spurts. I'm really having a hard time narrowing it down....especially since I'm the only one who feels it. My passengers look at me as though I was a nut case but I drive the car on the highway every day so I've become sorta hyper-focused.

I've often wondered if the problem is with the driver, not the car.

What you're experiencing sounds much more tangible.

Cheers
DD

 

Very. You can actually see the steering wheel shake at 30mph and anyone sitting in the car can feel the vibration

Still, I expect I'll get to the bottom of it sooner or later!!

I know what you mean though, when you work on the car yourself you do become hyper sensitive to change in any noise, smell, feeling in the car. Often it's caused by our own incessant twiddling