I’m looking for technical help or recommendations on: Clicking/clunking when reversing ND RF on full lock.
The car’s done ~42,000 miles. Never tracked, used year round enthusiastically.
When I reverse it on full lock, I have recently noticed an obvious clicking / clunking sound every 2 – 3 feet I reverse coming from the nearside front wheel area, which I can also feel through the steering. The noise only happens when the car is on the move, not when stationary.
I have lifted the nearside front wheel up on the jack while on full right lock. The wheel nuts are correctly torqued, there’s no free play of the wheel on the hub, and to the extent that I can see the various suspension components, there are no loose nuts & bolts – as you might expect on a 7-year old RF, they look nicely corroded together. The shock absorber appears fine, no weeps or leaks. Under the bonnet, the top mount looks OK, nothing loose as far as I can see.
Other than that the car drives and handles normally, with no such noises when on the move or when cornering, except when slowly on full right lock.
So I’m wondering what might be the cause and the cure please? What should I be looking for? Is it unsafe? Thoughts and comments welcome please!
I would try doing the manoeuvre with a little foot brake pressure applied and see if it changes.
It certainly would appear to be something rotational as the distance would roughly equate to one rotation of the wheels.
Any modifications or completely stock?
Is it only in reverse too or at full lock when moving forwards as well?
By any chance is 2-3 feet a full rotation of the wheel?
I would check the proximity of the wheel (barrel and outer tyre) to anything when at full lock on the floor.
It could be that something is catching on part of the suspension as it rotates.
Check that all wheel weights are also fully atatched.
Hmm, a full rotation is almost 2 metres, a bit more than 6 feet.
So a hop is more often than once a rev; then it does sound like the Ackermann effect mentioned by Bainbridge.
Another clue to this possibility is in the multi-storey where the road surface is usually glossy smooth.
Do they squeal on the tight turns? If so then it’s more of a continuous high frequency stick/unstick/stick/unstick… ‘hop,’ and much played up in the US movies to add drama and atmosphere.
Hop might be seen more with worn ball joints, squeal more with supple grippy new tyres.
But always consider the car’s natural characteristics first; it could simply be a case of “They all do that, Sir”.
Thanks for all the replies. Yes, it’s completely stock, with Michelin PS4s on the front which are down to about 4mm. It’s odd that it’s not happened before and those tyres have been on it for the last 3 years. I first noticed it about 3 weeks ago when reversing off my driveway into the road, something I’ve been doing several times a week since I bought the car 5 years ago.
Since then, it seems to have got worse, I noticed it doing it to a lesser extent going forwards earlier this week.
I’m getting a local garage to have a quick look at it on Friday just in case something’s worn or worked loose.
Well, the garage have lifted it up, had a good look and then took it for a test drive. According to them, nothing loose or worn or with excess play. They noticed the same as me on full lock. They put it down to a combination of the degree of wear on the tyres combined with colder weather.
