I have replaced the following on my XKR:

• Shock mounts with Welsh's urethane units
• Lower shock absorber bushing
• Bump stop
• Sway bar links

I torqued everything to spec.

After this work everything seemed mostly fine, until I drove the car on a particularly bad road at speeds below 15 mph. I can hear some loud clunks from the front suspension. After some more careful driving, I noticed that I can hear much more muted, almost imperceptible clunks at low speeds over some bumps on better roads at low speeds. However, this doesn't happen on larger speed bumps and nothing can be heard above 25 mph. This particular bad road has irregular bumps all over the place, as a result of an improperly done asphalt reconditioning.

I am wondering if my clunk was already present and was just being masked by the other stuff that I have now replaced. On my list I still have to replace:

• Lower control arm bushings
• Sway bar bushings
• Lower ball joints

My upper control arm bushings and upper ball joints seem to have been replaced recently as those bushings looked to be new.

Could these clunks be solved by the sway bar bushings? I can definitely expedite these instead of replacing them on February as I had originally planned. Is there an advantage of using Powerflex polyurethane over rubber for the sway bar bushings?

 

Sway bar bushings are a very common problem, not expensive and not too difficult to replace, especially if there is another pair of hands available. I would start there.

 

^^ What he said....

 

I agree with above, but FWIW I've got a similar noise from a bad upper shock mount. Diagnosed by measuring the distance between center of vfc wheel and lower lip of fender arch directly above. I don't have specs memorized but you can compare the 2 front wheels. Even an inch difference is failure. I think 15.5 inches is front spec but ez to just do a search here.

John

 

He has replaced them with the Welsh mounts, so that's not likely to be the problem. When I put new mounts on my 97 The ride height was lower on the drivers side, probably due to spring sag, so I ended up putting a 3/8" spacer in that side.

 

As RJ already said, I installed new urethane shock mounts last week. I haven't measured yet, but I'm pretty sure my ride height is at the correct spec. I'll be ordering the powerflex sway bar bushings. It shouldn't take more than a few hours to get those installed. I will also take the time to make sure that everything is torqued to spec. If the clunk persists, then its gotta be the control arm bushings or ball joints.


Btw, since I've got so little to replace for the front suspension to have it completely refurbished it, what should I be looking to replace in the rear suspension?

 

Spring pads and shock mounts.

 

 

The lower shock mount is a bushing, and much less expensive than the front one. There are also sway bar bushings and links, but they don't seem to take as much of a beating as the front ones.

 

So you think those are likely to be ok? If so, what is a spring pad?

 

After dealing with the front shock lower bushing replacement, I vowed to never again waste my time like that. What a PITA.

When I did the rear stuff I bought new shocks. I was shocked at how much the dampening was improved over the old ones that seemed fine. So much so that I plan to go back and replace the front shocks when I have the time.

I did the rear sway bar bushings well before I did the rear shocks but if you are doing the shocks that would be the time to do the sway bar stuff since you disconnect it all anyway.

My rear shock replacement with pics is here.

Rear sway bar bushing replacement with pics is here.

Worth noting that when I did the rear sway bar stuff it remedied nearly all the annoying drive train clunky sloppiness. Cheapest "significant driveability improvement" I made so far.

 

New rear shocks (October 2014) and new front shocks (January 2016) while Wayne (cjd777) and I were installing new shock mounts, upper control arm bushings, and sway bar links also made for a big improvement in ride and handling quality on my wife's 2006 XK8. As long-in-the-tooth as these cars are now, their original shocks are on their last legs regardless of the mileage on the vehicle....

 

My shocks are still excellent, probably also depends on the road surfaces. But XKR owners with electronic controlled shocks have to consider the cost of replacement. I replaced the rear bushings with a bench vice, a socket, and a short length of pipe, not difficult at all once the shock is out of the car.

 

I don't know how you fit them in there, but doesn't that give you a very clunky ride?

 

What he described is exactly the procedure I did for the front lower shock bushes. Once those are in, they're not moving out of there; it's a tight fit.

 

The socket and pipe aren't too bad, but the bench vise does bang around, especially on speed bumps.

 

 

 

Priceless. PMSL. Great start to 2019.