Jolting Clunk When Reversing In Full Lock.

[fiish]

Hi,

Today when driving home from town I had to do a reverse round corner to come out of some narrow roads. The corner was quite tight and I had to do the manoeuvre with the steering in full lock. As I was reversing, every 1-2 feet I would feel and hear a clunk from the front of the car. At first I thought I had hit something, but some passers by indicated nothing looked amiss. Then I thought I had not engaged reverse properly and went to neutral and reclutched before shifting and continuing the manoeuvre. There were a few more clunks which stopped after I straightened the steering.

Is this normal, or is there something wrong with the car mechanically? Have only had the car for 300 miles, really hope there is not another problem because the car otherwise drives well, and everyone I have ferried really likes it :)

[Cyker]

I've had this going forwards AND backwards when at full lock, but only if I'm in full lock for more than a brief moment (e.g. tight reverse round a corner or a tight U-turn, but not parallel parking).

Still don't know the cause, but haven't found any problems. Suspect it might be the CV joints or something in that area.

If I go REALLY slowly (e.g. speedo says 0mph) then it doesn't happen.

[GIDDLEPIN]

I get that on my roadster as soon as the weather turns cold and it is the tyres, same sort of worrying sound on full lock like yours, as soon as the tyres (or the weather) warms up it doesn't happen, you can try it yourself after a long run and if it disappears then it is the same, an annoyance but not a problem ;)

Les

[andycam06]

you only have the car for 300miles yea?

what size are your tyres and has the car been lowered?

sounds like the tyre is rubbing off the inner plastic arch, if this is the case you can buy a 5mm spacer from any motor factors or alloy place or about £5 each, throw them on and that should be you sorted

[GIDDLEPIN]

It's not a rub with mine, just tread snatch on cold tyres ;)

[Cyker]

you only have the car for 300miles yea?

what size are your tyres and has the car been lowered?

sounds like the tyre is rubbing off the inner plastic arch, if this is the case you can buy a 5mm spacer from any motor factors or alloy place or about £5 each, throw them on and that should be you sorted

Nah, it's not a scraping sound, it's more of a *clunk*-ing sound produced as the wheels turn.

Not sure if it is the tyres; Can't imagine how they could make such a sound, unless they're not parallel at full lock and that's forcing one of them to 'jump'/spring sideways as it gets pulled across rather than along...

The noise and thump is very similar to what my ABS was doing when it was trying and failing miserably to work as I slowly rear-ended a Ka (oo-er) last winter!

Edit: @Giddle - Tread snatch?

[Madasafish]

It could be:

a broken spring or the suspension top mounting faulty

a broken bush in the anti roll bar (not the droplinks).

a sticking brake caliper.

Worn rack mountings.

I suspect that when you reverse on full lock there is slight play in the wheel bearings. As the wheel reverses, the brake pads attempt to move in reverse direction: the rust/dirt stops any move, they stick and then release with a bang

The solution would be: remove pads and carefully copperease all pad surfaces which touch the calipers or guides. As evidenced by rust..##

(Mine occasionally bang if I have washed the car and the discs rust as I have not moved it after getting the disc surfaces wet)

## I always do that to any second hand car I buy for peace of mind.

[markweatherill]

I had something like this on a previous car, it was the suspension spring(s).

The top and bottom of the springs are seated in rubber cushions, and with the steering movement they get twisted a little as the top of the spring turns relative to the bottom.

Perhaps on full lock, one of them is shifting position on its rubber cushion inside the top or bottom mount. And when you turn the steering back, it'll clunk again.

[Madasafish]

I had something like this on a previous car, it was the suspension spring(s).

The top and bottom of the springs are seated in rubber cushions, and with the steering movement they get twisted a little as the top of the spring turns relative to the bottom.

Perhaps on full lock, one of them is shifting position on its rubber cushion inside the top or bottom mount. And when you turn the steering back, it'll clunk again.

I did spray mine with WD40 years ago..

[Raeman]

Hi,

Today when driving home from town I had to do a reverse round corner to come out of some narrow roads. The corner was quite tight and I had to do the manoeuvre with the steering in full lock. As I was reversing, every 1-2 feet I would feel and hear a clunk from the front of the car. At first I thought I had hit something, but some passers by indicated nothing looked amiss. Then I thought I had not engaged reverse properly and went to neutral and reclutched before shifting and continuing the manoeuvre. There were a few more clunks which stopped after I straightened the steering.

Is this normal, or is there something wrong with the car mechanically? Have only had the car for 300 miles, really hope there is not another problem because the car otherwise drives well, and everyone I have ferried really likes it :)

Sister in law just had to have a new driveshaft in her Corsa, same symptoms as you are having, she thought it was the CV joint but alas...

Good thing was it only cost her £197 instead of the Vauxhall dealers quoted £400!

[fiish]

My Yaris has not been modified in any way, it is the standard spec with 15" wheels and the OEM tyres.

After filling up yesterday morning (first fillup since buying the car :) ) I took the car to a nearby (< 1 mile) service station's tyre pump and repressurized the tyres as I thought they might be a bit soft. I had to do a full-lock reverse to get out of the air and water bay in the service station, there was still a clunk but it was much softer this time and there was only one throughout the turn. Also when I got to work and full-lock reversed into a parking bay there was no clunk.

I think I shall continue driving the car and see if it stays in this better state. If it does turn out there is a mechanical issue though, would it be classed as wear and tear? (I ask because I have a warranty to 2013 on this car)

[andycam06]

no well either way you only have the car so they cant call it ware and tear after only a few weeks.

well i was reversing my womans vitz (yaris) last night and for this purpose put on a full lock, every couple of seconds had a wee cluckish noise, but mine was just the steering pump under pressure with the full lock, this this maybe be your issue ?

[Raeman]

fiish, i would imagine the warranty will cover it. Ring your dealership if in doubt to find out.

[GIDDLEPIN]

Reversed out of the car park when leaving work tonight, guess what?....Every 1-2 feet it made a loud clunk and the whole car juddered with each clunk (sound familiar?), not the springs, suspension, brakes or drive shafts (RWD ;) ).....Yep, it was the tyres....again.

As with all advice given by myself and others, this is all it is....Advice At the end of the day diagnosis and any rectification will be down to you or the (hopefully) responsible party who correctly diagnoses the problem without to much cost ;)

Les

[Nath_c]

That coulld be something along the lines of a CV boot if its only when in lock, however i thought i would post this as a different area to look into. I appologise if someone has already posted this idea, but i have a 2001 P1 T-Sport. I started experiencing a knocking and a jolt when engaging into reverse, but not always only occasionaly. I assumed because my release bearing on the clutch had gone (apparent common fault) that this was one of the symptoms. However i was told by a trusted garage that this could well be a engine mount, which is why it only sometimes does this, and other times the engine is sitting properly, i was told another symptom of an engine mount failure is small "wobbling" or vibration when idling.

[fiish]

I am starting to lean towards thinking this is a tyre related thing, particularly since it has seemed to have lessened after reinflating my tyres properly. At least on today's evidence, anyway. Reversed in full lock at work car park, no clunks. Reversed at supermarket car park, no clunks. However, there was (softer than when I started the thread) clunking both forwards and backwards when I drove to a friend's and had to do a 3-point turn on a slightly uneven brick paved road. Seems like the driving surface also plays a part (and I would not be surprised if slippy, icy surfaces did too).

[Andy_R]

Mine is doing this too - exactly the same symptoms as described. Has anyone found out a definitive answer to this yet? My Yaris has been in to the local dealers twice now, and they've not found any fault or been able to replicate the situation.

[fiish]

Try reversing in full lock in a wet parking lot and have just one tyre go over a drain cover (or something more slippery than the road). If you get a clunk only from the wheel you expect to slip, then the tyres are probably the culprit.

I also found that getting my tyre pressure right improved things, eliminating clunks in some places and generally making them softer (and less distressing).

[Cyker]

I'm almost convinced Giddy's right about it being the tyres.

On high-grip surfaces it's the 'thunk' is much more forceful, but on slick surfaces it's barely noticeable.

[GJK]

Hi, My Yaris is 2.5 years old and I've had it from new, but it has just started the clunking noise when reversing, as described above. It's in with the dealer at the moment but they can't replicate the problem either. The AA thought it was something to do with a panel behind the front wheel, driver's side. Any further thoughts anyone would be gratefully received.

[Long-suffering husband]

Clunking Lexus in Reverse Turn

The reason for this worrying noise is because your brand new front tyres are what we engineers call `stiff' i.e. not very willing to do what you want them to do when they much prefer be doing their own thing.    Which is to roll in a straight line (and is just what you want on the motorway).    When doing a reverse tight turn, the tyres resist the growing urge to follow the tight arc you are steering, until the pressure to conform becomes overwhelming and the tyres are forced to scrub round to align with the arc you are imposing on them.    They then align suddenly with a thump until another re-alignment is needed further round the arc and you get more thump(s).   So there is nothing to worry about other than the fact that such tight turns even at low speed cause scrubbing that wears your tyres far faster than miles of going straight.   

There is nothing wrong with your car or the new tyres.    If it really does bother you, sprinkle some sand on the road aa this will help to the tyres to scrub round more easily (either by weakening the grip between tyre and road or by smoothing the micro hills and valleys of the road surface).

Either way, it works as I have just checked by fixing the clunks on my wife's Lexus.     Was she grateful..........what do you think?    She now has to walk round the front of the car to avoid the sand! (But even worse, now has to call the garage and cancel the appointment to fix the noise).

[ashu]

On 1/9/2022 at 2:45 PM, Long-suffering husband said:

Clunking Lexus in Reverse Turn

The reason for this worrying noise is because your brand new front tyres are what we engineers call `stiff' i.e. not very willing to do what you want them to do when they much prefer be doing their own thing.    Which is to roll in a straight line (and is just what you want on the motorway).    When doing a reverse tight turn, the tyres resist the growing urge to follow the tight arc you are steering, until the pressure to conform becomes overwhelming and the tyres are forced to scrub round to align with the arc you are imposing on them.    They then align suddenly with a thump until another re-alignment is needed further round the arc and you get more thump(s).   So there is nothing to worry about other than the fact that such tight turns even at low speed cause scrubbing that wears your tyres far faster than miles of going straight.   

There is nothing wrong with your car or the new tyres.    If it really does bother you, sprinkle some sand on the road aa this will help to the tyres to scrub round more easily (either by weakening the grip between tyre and road or by smoothing the micro hills and valleys of the road surface).

Either way, it works as I have just checked by fixing the clunks on my wife's Lexus.     Was she grateful..........what do you think?    She now has to walk round the front of the car to avoid the sand! (But even worse, now has to call the garage and cancel the appointment to fix the noise).

You just saved my day. My wife's lexus is doing the same and her warranty runs out day after tomorrow. I still don't fully understand why it makes that noise but I am relieved greatly. And by the way, about wives being grateful ? You are not alone!!