Ls400 Mk3 Handling & Geometry Question

DLarkin · May 13, 2005

After a year of looking Ive just bought my first lexus, a FSH 95 LS400 with 160k on the clock which I am really pleased with. It has a few problems which I was aware of at the time and Im having some trouble deciding which bits to sort first.

Im getting a light but annoying vibration in the steering wheel around 55-60mph. So, I Got front wheels balanced today and the vibration is still there, however I couldnt be 100% sure that the garage I used were 100% accurate, the car also has 17" whellmania alloys with 235/45/17 tyres and I have to assume the previous owner did not have the geometry checked & adjusted.

Could there also be offset problems, how can I tell as the handling while excellent is not just as good as other ls400s I have driven. It wanders a little and I know I can feel and hear a light rumble from the front on more uneven roads which I am assuming is confirming the Jan/05 Service report which indicated there was some grease leaking from the O/S/F ball joint and some play in the track rod

My thought was to Replace ball joint and track rod on one (or should it be both sides), I intend ordering the parts from the states so this is a few weeks away, and then look at geometry or could a geometry check first be useful in diagnosing any other potential problems.

Many thanks

declan

simontaylor · May 19, 2005

1/ If the vibretaion is felt in the steering wheel you could swap the fronts with the rears?

2/ You can measure the off-sets, crudly your-self. Take eah wheel in turn (spare as well), place it on the ground outside down (maybe on a piece of carpet to protect it), put a straight edge accross the wheel's diameter and measure the distance from the straight edge to the wheels face where it would sit on the hub. As the tyre bulges out, for your straight edge, use a piece of wood that is cut down so that both ends sit on the wheel rim, otherwise the tyre walls will generate all sorts of inaccurate readings.

tangray1 · May 20, 2005

1/ If the vibretaion is felt in the steering wheel you could swap the fronts with the rears?
2/ You can measure the off-sets, crudly your-self. Take eah wheel in turn (spare as well), place it on the ground outside down (maybe on a piece of carpet to protect it), put a straight edge accross the wheel's diameter and measure the distance from the straight edge to the wheels face where it would sit on the hub. As the tyre bulges out, for your straight edge, use a piece of wood that is cut down so that both ends sit on the wheel rim, otherwise the tyre walls will generate all sorts of inaccurate readings.

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Hi again mr larkin (lpg inq)sounds like my car when I bought it and had all sorts of vidrations through steering and transmisson, .Firstly sort your braks out LS`s eat front disc`s for fun and I bet your front calipers are seizng up as well ,very common but overlooked and this causes your new discs to warp !!!

THen sort your rear suspension as on LEXLS.com web tutorials. i have replaced all my rear suspension bushes for poly bushes ,still a superb rde quality but alot less roll, and much better road holding.

DLarkin · May 30, 2005

Thanks for the replies folks,

Getting to the bottom of the vibration took a little time with 3 balancing attempts by different garages, I got some advice from Tony aka (wheelsinmotion) who suggested I needed the balancing done on a 5 stud plate.

Couldnt find anyone with a 5 stud plate but found a local alloy wheel specialist and it turns out the spiggot rings were missing from one side of the car, he put 2 new ones on but there is still a little play there so I still dont think these rings are exactly the right size.

Anyway the vibration has been reduced to almost non-existent.

Tangray, Where did you get your poly bushes? I think that might be the next maintenance item on the list

LEXTORIA · May 31, 2005

Got vibration on my car at around 80-90 mph. Been back to the garage three time and it has made little difference-it was perfect before they put the new tyres on grrrr!!!

Will try another garage methinks ;-)

LEXTORIA · May 31, 2005

By the way, what's a spiggot ring-I don't see any rings on my wheels??

DLarkin · May 31, 2005

You only need to be concerned with spiggot rings if you have aftermarket alloys. Heres a link that I found useful for explaining the terms

Alloyguide.co.uk

If youre getting a vibration at 80-90mph that just started when you got the new tyres it doesent sound like a balancing problem,...... its most likely your new tyres