TechBits #1 - Diagnosing Front End Noises on Jaguar XJ6 and XJS
Jaguar Parts Technical information
Does the front of your car rattle and clunk when you drive over a rough section of road? Or, do your tires wear out along one edge? It's time to take a look at your front end. There are two common culprits when these things happen.
The first culprit is the upper shock bushings. These hard rubber rings isolate the shock absorber from the car body, and when they wear out the shock bolt starts to bump against the car body. This is the first thing to check when you hear a noise when you drive over a bump. If yours are squished out of shape or are missing, replace them, but only replace them with factory shock bushings. Aftermarket shock bushings are too hard and cause the metal mounting point to flex and eventually fail ($$$). The factory parts are cheap enough.
The next part to check is the upper ball joint. This requires two people. Place a jack under the lower spring pan, and jack up the car just until the wheel is about an inch or two off the ground. Grab the top and bottom of the tire and lift up, trying to rock the whole wheel up and down. At the same time, also try to move the top of the tire in and out, as though you were trying to rotate the tire up and lay it on top of the engine. While one person does this, the other person should be looking at the upper ball joint with a flashlight, trying to identify any movement. There shouldn't be any. If there is movement, replace both of the upper ball joints. Bad ball joints will cause the inside edges of your tires to wear faster than the outside edges.
Since you're checking things, take a few moments to have a look at your tie rod ends. This is the part where the steering rack hooks up to the front wheel. With a partner turning the steering wheel back and forth, look for play or looseness in the two tie rod ends. If there is any, replace them too.
See our Jaguar Parts Store Catalog to order parts.