Greetings Everyone:
Just left the same question by accident in the XJ forum for 2003-09.Recently joined the forum and was moving a bit too fast!! So startting over: I am proud owner of 2002 XJ8 VDP/Slate Mica Grey with beige interior. A beautiful car with 82,000 unmolested miles. I spent some serious coin for mechanicals and body work..and am so happy. It's a rolling work of art! Now that I am driving it every day just noticed one thing: some vibration in the steering wheel and body at idle and low speeds/low throttle...not horrible mind you...and a related soft engine drone at 50mph that goes away at lower and higher speeds. Do XJ8's need engine and transmission mounts replaced periodically? This isn't a major complaint but the car is so smooth and silent the harmonics and vibration stand out. It's as if the mounts are metal on metal. Thanks for any suggestions or advice. Just love the car!

 

That MIGHT be a sign of the torque converter slipping when it is supposed to be locking up. I have the same slight noise in my wife'e XJ8. It is not enough for her to notice, so I have been waiting for it to get worse. It has remained about the same for 40, 000 miles, which included a set of new tires and a brake job. So, if you figure it out PLEASE tell me what you find!

 

The classic test for broken motor mounts is to open the hood and do a brake stand. If the motor rotates .. the mounts are toast. Usually the left mount which is the hardest to get at.

 

Thanks so much guys!....will let you know when I find out...

 

Do you have good compression all around? I have low compression in one cylinder and it gives me a rough idle and a engine vibration around 50 mph. I can use the J Gate to shift down (at around 50 mph) and avoid the vibration then just back into regular drive when over 60 mph.

I doubt your problem is as serious as mine but figured I would throw it out. BTW, the compression one of my cylinders is very low but the engine actually run pretty strong.

Looking to swap engines or just swap the whole car.