Ls430 Full Lock Knock

[northern royals fan]

I've a 2000 LS430 with 116k miles on it. It has been brilliant for years. But now it has developed a knock when on full lock. I have a tight drive so get the knock, a single sharp crack, regularly.

None of the local garages can work out what it is. Has anyone here got/had a similar problem or have any ideas what it is?

Thanks

[Manc]

I was going to suggest the front control arms / bushings / balljoint...

but if you say the garage doesn't know then i dunno.....im sure they would have picked that up as parts move a little more than they should...

Thats how mine started to go when turning out of the drive, i'd get 1 or 2 sharp loud knocks.......then it developed into a few creaks/groans over the bigger bumps / kerbs on the road, then every dip made a noise after 2 weeks...

it was the bushings that went but i needed new arms....

take it somewhere else and ask them to check the front bushings...

is your brake disc cover okay? these can sometimes catch if they have seen some miles

[passman53]

Hello,

Look in Lexus Workshop, page 2-Caliper slide pin replacement article by Tigerfish. The noise you describe sounds just like I had on my Mk 4, a single loud(very)crack, and these turned out to be the culprits. This was about 3 years ago and at the time the new ones from Lexus were around £20 each.It appears that you can get a rust spot that causes the pin to stick.

Hope it turns out to be as simple as this on your car.

Pete

[northern royals fan]

I was going to suggest the front control arms / bushings / balljoint...

but if you say the garage doesn't know then i dunno.....im sure they would have picked that up as parts move a little more than they should...

Thats how mine started to go when turning out of the drive, i'd get 1 or 2 sharp loud knocks.......then it developed into a few creaks/groans over the bigger bumps / kerbs on the road, then every dip made a noise after 2 weeks...

it was the bushings that went but i needed new arms....

take it somewhere else and ask them to check the front bushings...

is your brake disc cover okay? these can sometimes catch if they have seen some miles

Thanks Manc. I don't know if there is a problem with the covers. The disks and pads have just been done, so I would assume that they are fine.I was also wondering if it might be wheel bearings.

[northern royals fan]

Hello,

Look in Lexus Workshop, page 2-Caliper slide pin replacement article by Tigerfish. The noise you describe sounds just like I had on my Mk 4, a single loud(very)crack, and these turned out to be the culprits. This was about 3 years ago and at the time the new ones from Lexus were around £20 each.It appears that you can get a rust spot that causes the pin to stick.

Hope it turns out to be as simple as this on your car.

Pete

Thanks Pete, I might just try this line in any case, as it does seem to be a regular problem. But I was also thinking it might be wheel bearings. Any thoughts?

[The-Acre]

Hello,

Look in Lexus Workshop, page 2-Caliper slide pin replacement article by Tigerfish. The noise you describe sounds just like I had on my Mk 4, a single loud(very)crack, and these turned out to be the culprits. This was about 3 years ago and at the time the new ones from Lexus were around £20 each.It appears that you can get a rust spot that causes the pin to stick.

Hope it turns out to be as simple as this on your car.

Pete

Thanks Pete, I might just try this line in any case, as it does seem to be a regular problem. But I was also thinking it might be wheel bearings. Any thoughts?

Having experienced the knock from caliper slide pins and thinking it was something really serious, I'd certainly check that out on the side the knock's coming from. I'm no expert but I would have thought you would know about it if the wheel bearings were worn enough to make a crack/knock.

Phil

[mikesands]

Don't suppose you have fitted new tyres lately have you. Mine had a knock on full lock when I bought it. Lexus then realised that the previous owner had fitted 235 tyres (I think) rather than 225. They were OK on the rear but not on the front.

Mike

[northern royals fan]

Don't suppose you have fitted new tyres lately have you. Mine had a knock on full lock when I bought it. Lexus then realised that the previous owner had fitted 235 tyres (I think) rather than 225. They were OK on the rear but not on the front.

Mike

Hi Mike. Tyres are all good. I think it must be brake or suspension related. Thanks, Richard

[northern royals fan]

Hello,

Look in Lexus Workshop, page 2-Caliper slide pin replacement article by Tigerfish. The noise you describe sounds just like I had on my Mk 4, a single loud(very)crack, and these turned out to be the culprits. This was about 3 years ago and at the time the new ones from Lexus were around £20 each.It appears that you can get a rust spot that causes the pin to stick.

Hope it turns out to be as simple as this on your car.

Pete

Thanks Pete, I might just try this line in any case, as it does seem to be a regular problem. But I was also thinking it might be wheel bearings. Any thoughts?

Having experienced the knock from caliper slide pins and thinking it was something really serious, I'd certainly check that out on the side the knock's coming from. I'm no expert but I would have thought you would know about it if the wheel bearings were worn enough to make a crack/knock.

Phil

I had the slide pins done. One each side on this model it seems. Although it did appear to better at first, the problem is back as bad as ever. I think I'm going to bite the bullet and have a look at them myself, and possibly put a new set of OEM pads in. I don't want to go the whole hog and do the discs as well.

Thanks

Richard

[steve2006]

Another thing that could cause the problem is a broken spring, this can be difficult to see as breaks normally occur right at the top or bottom coil which are normally hidden by the mounts.

Years ago I remember cases where the springs wound up under full lock then suddenly released giving a sharp crack as they did.

Just a couple of ideas you may want to look into.