Hi, hoping someone will have an idea

My XK started producing a cracking noise in the following scenario:
- I'm steering left at parking speed / standstill OR I'm beginning to steer right from left lock (no noise yet)
- I start to move (really slowly, let's say brake is 70% depressed where 0% is no brake/no gas speed and 100% is standstill at traffic lights)
- some tension is let go resulting in a crack that's coming from the front of the car

The condition happens intermittently (30-40% of the time), the further left the steering goes, the bigger the chance.
When going backwards it also happens more often.
It doesn't seem to happen when steering right / returning from right lock.
It also doesn't happen when the car is jacked, only when the car's weight is applied to suspension.

I think I can feel the crack on the steering wheel but it always gets me by surprise so the feeling might just be my reaction.

My indy has been at it for half a day and didn't find anything. Both me and the indy were able to reproduce the sound but couldn't find the culprit.
Said everything is in perfect order apart from banana control arms bushings having slight play (not warranting replacing them yet, not obviously related to the sounds).
They also ruled out mcpherson bearings which was my first suspicion.
Steering fluid is newly flushed and replaced.

Yeah, I know I shouldn't steer at a standstill but IRL parking spaces are sometimes microscopic. It's seems to be a new thing too.

Does anybody has some idea what might it be?

 

When turning, the sway bars and suspension at all corners are under pressure.
Therefore, so are the subframes, should those bushings be worn...

 

Our XK does that when you move slowly at full steering lock. There is no play in any of the bushes and it happens a lot more easily in winter when the tyres are cold. I've come to the conclusion that it is the tyres intermittently grabbing when being pushed forward at full lock. The tyres actually need replacing as they are rather old and virtually down to the wear bars so I think this is exacerbating the effect. I've checked the tracking and it's not due to that being out. It does not happen on gravel as the tyres slip easily without grabbing.

Richard

 

Need to test on gravel then.

I bought fresh new tyres this season, Conti SP7, they still have 6.5mm (as they leave the factory) at the fronts. They grip like hell, best tyres I've ever had but I'd be surprised if this was the culprit.

Will see though, thanks for the suggestion

 

Second possibility: Left wheel bearing....

 

Can you post a short video of the sound you are getting?

 

@sony2000 Doubt it's the bearing, there's no vibration at any speed, handles like a dream. Recently replaced right bearing which caused very specific vibrations, I'm kind of oversensitive to this kind of thing now.

@RichardS On gravel, the sound was much less pronounced but still audible. I think this rules out the tyres - some tension is still causing the sound and I don't think gravel can be grabbed by tyres in such a way.

@neven.gordic in 5th second, the louder crack is the one I mean. In the vid, it was quite dull comparing to the real thing.

 

Usually the worn bearings don't vibrate. "Recently replaced the right bearing". So its the time for the left bearing to wear out.

 

@sony2000 I replaced the right bearing because it's been damaged but left being worn is a possibility. Would it exhibit play when jacked or not necessarily?

 

Rarely shows play when jacked unless very worn out. MY left wheel has play, but am changing the tie rod ends today. Because of you I thought of tightening the wheel bearing.

 

So in my case the fix could be as simple as tightening the wheel bearing?

 

tightening?? or REPLACING

 

Replacing is what I'd expect to have to do but @sony2000 mentioned tightening, hence curiosity

 

Bracgacz, you have an issue. Wear. So tightening is not a solution. I should have added, that it was a bogus thought to be ignored.

 

For someone who stumbles on this thread in the future.

The issue was the front subframe that had been adjusted to a wrong position. In fact both subframes had opposite tilts relative to vehicles back-front axis.

After readjustment the noise seems to be gone for good and handling again feels like a proper Jag.

 

the update is much appreciated! Mine is in for a similar noise check. If they get stumped I will share this with them. Can you tell from a vehicle alignment report ( done in July) if the sub frames are incorrectly adjusted?

 

That's the kicker - alignment sheet won't tell you if subframes are positioned as they should, all the measured angles on the alignment sheet were in tolerance, hence the confusion.

TBH my subframes were messed with before but I assumed the people who did that knew what they did. As always, wrong assumptions are the root of all evil.

Full context:
- I was in a crash - https://www.jaguarforums.com/forum/x...-total-274711/
- everything listed by the main dealership was replaced including full right rear suspension area (except for the spring and subframe), car is back on road
- numerous little discrepancies were fixed (vibration vs front right bearing, braking vibration vs rotors + pads etc etc)
- somehow after the fix, the rear axle seemed "shifted" ~1cm to the left relative to body. Meaning left rear wheel seems to fill the arch much better/fuller than the right - side that was hit the worst). Alignment sheet was in spec (in theory) but visually it didn't look right.
This is visible in the photos in this post: https://www.jaguarforums.com/forum/x...2/#post2751437

Took the car to a shop specialising in alignments, they adjusted both subframes to negate this effect.

Visually it was ok but I could feel the behavior of the car was strange at times over the next couple times + the creaking described in this thread.
Strange as in eg some weird oversteer on straight when accelerating hard on highway after leaving merging lane (same situation sure as death and taxes before the crash). As for the creaking, I couldn't tell at the time if it was a new thing of one of many that surfaced after the main rebuild / sitting on dealers lot for a couple of months.

Recently I had all rear left control arms and rear right with respective bushings replaced (because of their age/condition) and had the subframes moved back to their tolerances.
Indy told me the rear one was tilted to the left side of the car, front one to the right... no wonder feeling was off.
Boy is it a dream to drive again, I'd say better than before the crash 8)

Creaking is gone, just this "axle shift" remains, not really sure what to do about that.

 

Thanks for providing the summary @Brachacz . Like you, I’m always surprised by those purporting to be professionals and in their haste? miss the necessary QA.

I was under the impression that the modern, laser assisted, frame/subframe aligning/straightening gigs were dummy proof.

 

Guess I was blessed. Just the underside fender cover loose and rubbing a wheel👍