HI, 1996 XK8,had a problem with the back end being unstable,hitting a slight bump will make the back end skip and seems unstable on cornering and stability and traction control warning was on,so had new shockabsorbers fitted all round ,bought from jaguar supplier,the fronts original jag parts the rears are bilstein(assured they are original equiptment)after a couple of months took it to the local jaguar dealer as the stability and traction warning was still coming on and the car was still skittish on the back end,they told me the rear shocks were bad again,so they were changed under guarantee, no real improvement,traction control light and now they are scratching their heads ,could anybody give me some clues ?as i am not convinced the problem lies with the shocks.

 

Mike, do the XK8's come with a limited slip unit in the rear axle? Looking at the drawings inside of the JTIS, it appears it does. If the limited slip unit has failed (ie, is now acting like a locker), that can cause the skipping you are seeing in the corners since both rear tires are trying to spin at the same speed even though they are travelling different distances. This could also cause the traction control to sense there is a problem because now it can't control each wheel independently.

This problem could be also something as silly as not using the correct lubricant in the rear axle. Limited slip units require special additives to make them function properly. I have a limited slip unit in my truck and if the amount of additive gets too low, the rear end will act like you are describing (I don't have traction control on the truck, so, that is something different).

Hope this helps get you to your answer.

 

As far as I know the XK8 does not have Limited slip, only XKR does if it does. I remember my cat being on the lift and spinning one wheel the other was spinning the other way or something like that.

How about your tires? Are they in good condition? Are they good brand?

One of the cars at work is a Mercury Grand Marquis, has pretty crappy tires and Traction Control. Whenever I go over a bump without letting the gas off it will slip and activate the TC, also on turns hard on acceleration or tight corner tires slip and TC come on.

That's just my 0.2$ hope it helps. Oh do you get Stability control fail at all? Could be your ABS sensor or Harness going bad triggering ASC.

 

What wer ethe faults in the abs dsc? If any. If none i would look really hard at the tires. They should be same brand very similar tread depth (a worn tire on 1 corner will rotate faster and make the asc think theres tire slippage, and this is mostly going around corners) also the rear tires on the xk are large than the fronts and ive seen people rotate and not pay attention to this or when replacing tires and put rear/front tire size all the way around. Also if you use differant tire brands but the same size, there can be a very large differance in the diameter even though theyre the same size. This too leads to overly sensitive asc. Skittish over bumps. Personally i think all xk's exhibit this to a degree in my opinion