Can anyone hlep me before I take the car to Lexus. Problem starts about 70mph and continues to worsen as speed increases, the car starts to judder and vibrate. All wheels have been recently balanced. 1998 GS 300 SE - still has 10 months warranty. Any help would be appreciated.

Check engine mounts.

Don't really know much about cars - is this a big prob if it is the engine mounts?

It's always wheel banacing mate - take the car somewhere else for a second opinion

still reads like wheel balance to me? how well are the tyres wearing? what method of wheel balance as for as the type of mount was used? when did the problem appear was it all of a sudden, a little bit and getting worse, have you just had some work done on the car?

I have only had the car for 2 weeks - wheels were taken off the car and balanced by local independent tyre depot

the method of the balance is my interest, the way that the wheel is mounted on the balancer is the point, the wheel must go on to a studed plate, this uses the same way of mounting as there is on the car useing the stud holes, not the wheel centre as this is cosmetic in design and my be off centre?

Sounds to me as well as wheel balance is out due possible to a lead weight comming of a tyre while on the move it does happen. other thing to check for is free play in the steering unlikely but worth a mention.
Realspeed

Sticky brake piston. Check the front pads are wearing evenly.
I had my tracking done, wheels balanced, bearings adjusted, tyres swapped around, balanced again and it was the caliper all along.

Rodders says 'its always wheel-balancing' and he is usually right with his responses on this forum.

My GS wheels were balanced twice by Costco who supplied the tyres and still wobbled at speed.

Took the car to Lexus Hatfield who used their own state-of-the-art kit to rebalance. Result - no wobble.

In my experience the GS is particularly susceptable to correct balancing.

Found this on mine aswell - at around 60Mph, there was steering wobble. Re-balance never made much difference but there was a few bits that did make a difference - check for a slight amount a disc wrap, this was the case on mine and also when you removed the wheel, was the hub and the back of the wheel cleaned off? any dirt will make a lot of difference seeing as that the wheel will not go back on in Exactly the same place, just by rotating the wheel and placing back on could give wheel wobble.

Did all this and now the car is like an arm-chair on wheels at any speed.

Thanks for all the responses so far - a friend of mine has mentioned Demon Tweeks (Wrexham) who will do a "proper job" of balancing the wheels - anyone had any experience of them ????

Just had same problem with mine but it was due to inaccurate wheel balancing.

Had wheels balanced twice but same problem.

Changed front wheels to back and all rebalanced by ATS, problem solved. Also has a fat spot in one of the tyres which also aggrevated the problem.

So like the rest of the replies will have to say go to a decent tyre place to resolve.

My IS started shaking from 70mph worsening as speed increased. Thought my wheels would need balancing but turned out just to be tyre pressures. 3 out of 4 tyres under inflated. Corrected and now floats on air.

My lex got the shakes just after a lexus service,after a few weeks i got fed up with it and decided to explore.It turned out to be a missing wheel nut.The only people to touch them is GUESS.

Once got mine done twice by one company who insisted their machine had just been calibrated, they'd done a Rolls that day etc. Still got vibration so took it to another place and they balanced them fine. Second company said the first had used cheap weights.

Had similar problem on my 98 GS few months ago. Had front tyres tracked & balanced, and was diagnosed by 'tyre specialist' as wanting wheel bearing.

Took 4 a second opinion, to find wear on inside of one of rear tyres, verging on egging, to be the problem. Didn't think this would affect to extent of the wobble I was getting, but it did.

Ste J.

Hi ya Ste. Still Lexing ?

***UPDATE*** - had no furher joy at local tyre/wheel places - managed to get the car to Lexus (Chester) - quick test drive - Tony told me that is was definately the wheel balancing - car booked in for full balance on Saturday - can't wait for the results and will update then. By the way - wobble disappears at about 90+

Finally sorted - Rodders was spot-on - wheels balanced by Lexus - £30.00 - now got 100mph lounge on wheels (infact it's far nicer than my lounge)