In the last 12 months of ownership I have been slowly sorting out annoying problems with the car.
The worn items that I have replaced for genuine Jag parts are as follows,

Rear upper control arms (fitted Volvo adjustable arms).
Rear lower control arms.
Rear forward hub bushes.

Front arb bushes.
Front drop links.

The rear dampers are good, and the rear drop links and bushes are good also.

The front wishbone arms are ok with no play, as well as lower ball joint and bushes, all bolts are tight.

The problem I have is when going over a pothole the car makes a sharp knock/ cracking noise.
I cannot find any movement in both front and rear subframe bushes, also the front top damper bearings make no noise when turning steering, and the top bush has no movement detectable of the damper rod nuts.

Any good advice ?

Paul.

 

I had this twice. First time was the A Frame assembly (ball joint one). Recently, it was a loose nut on the Front Stabilizer Sway Bar End Link. It had somehow backed half off the bolt. Idk how with the way it tightens with a torx in the bolt while tightening the nut. Last place might be the bar it attaches to and bushes are shot (goes driver's to passenger's side). That loose part in mine let it bang.

 

Part 1x43 5494 AB

 

Hi Dell,
Yes I replaced those insulator/bushes on the subframe that holds the anti roll bar.

Paul.

 

Could it perhaps be strut (bushing or loose mounting plate)? Or struts failing?

 

This part =

 

Could be a bad spring or the rear sway bar.

 

• The rubber bushing cushions the strut rod from the strut tower. When it's hard and compressed with age, the strut clunks over bumps. To test, find a speed bump you can hit one tire at a time and listen for a clunk as you drive over it at ~5-20 MPH (depends on the car and size of the speed bump).
• The bearing rotates +/- ~45 degrees as the front wheels & strut assembly turn right / left. A bad strut bearing won't turn freely, so the strut clunks when the steering wheel turns wide swings. To test, turn the steering wheel lock to lock at ~5 MPH in an empty parking lot.

If you replace the strut mounts, consider replacing the struts also, since both must come out for this repair.

This post has pictures & a video:
https://www.jaguarforums.com/forum/x...8/#post1086581

 

If the struts need to be replaced I would option to have the springs replaced as well. No additional labor in involved.

 

Thanks for all the suggestions.
There is a threshold where the severity of the pothole causes this hard knock, it is too severe to be anything like drop links.
The harshness of the sharp knock is definitely sounds like direct contact with the main body.
Interestingly though, front road noise seems excessive, it does quiet when the road changes to smooth tarmac.
Regarding front struts, I have done struts before some years ago now, and I still have some spring compressors in the garage.
The top bearings have no noise when turning, also the top strut rod nut does not move up or down when bouncing the front of the car, looks like I will have to jack up the front end and pry the front wheels up and down to see if the top bush moves when the weight is off the strut.
I have considered subframe bushes, but I cannot find any obvious play.

Paul.

 

That part also moves laterally as wheels are turned (i.e. Pothole tries moving wheel left/right). All else having been checked and eliminated, I'd still guess the strut mount/bearing. You can have someone sit in the car and turn wheel lock to lock while looking at the top of the strut under the hood to see movement. I just don't think you can get it to move sideways fast enough doing that to see/hear it hit.