When I first got my XJ it would track down the highway beautifully--never deviate from a straight line and only require minor steering corrections. Around 65k miles it started getting very drifty on the highway, it actually happened suddenly during a long trip. First I got new tires, as the old Contis were hard and worn out. That did help, but not completely. Then I replaced all 4 tie rods, as the originals had boots that were completely trashed (and an alignment). That also helped a lot, but it's never been as good as it once was.

Now I have a clunking from my rear suspension. I haven't gotten the car jacked up to pry around, but I'm thinking it's the lower shock bushings based on the sound.

I know the rear lower control arm bushings have torn rubber boots, but I've pried on them before and never found any play. Is there any better way to diagnose a loose or worn bushing short of just replacing them all?

My front suspension is silent, but if the front lower bushings (the large rubber ones under the radiator) were getting aged, would those be likely culprits for steering wander? There's no play in the steering wheel/rack that I can feel... it's just that on a straight road, the car will suddenly drift and I will have to correct for it. Used to be immune to wind, now it will wander in crosswinds as well.

I've never had any luck prying on bushings or ball joints and finding the bad one, unless it was patently obvious and had 1/8" of play.

Thanks,
-Michael

 

At that sort of mileage, (65k), I would expect the rear lower wishbone bushes to be worn out, and this can result in the rear wheels "steering" the car. Of course the inner bushes on the front wishbones could also be worn-out too, but as my car is on 86k miles and I had to have new rear wishbone bushes but fronts are OK, I think your problem is at the rear. The upper wishbone bushes front or rear don't seem to wear out so quickly.

Other bushes with a short life are the lower shock/spring unit bushes. There are four of these and they take the full weight of the car. ABout 35k miles is normally enough for them. Poor Ford design I'm afraid, but the bushes themselves are cheap and replaceable.

I would also suggest you have a 4-wheel alignment done at a shop with the expensive equipment needed to make a full check. Caster and camber are checked on the latest modern equipment, and will extend the life of the tyres greatly.

Check the rear track rod bushes too.

 

Thank you Fraser, that's actually very helpful. I had a friend drive the car today as well, and he agrees the back end feels like it's out of control and affecting my steering. I will start with the lower shock bushings and then do the lower control arm. Actually my car is pushing 88k miles now, so the lower shocks are long overdue.

Where did you source your LCA bushings? I know they're only aftermarket, but don't seem to have a good list of places. Did some searching and found Racing Green Jaguar (The Jaguar Shop. Online parts & accessories.) with pairs for £50 per set. I'm not sure who else makes them or what quality differences there are.