marksexton

I posted a few weeks ago about buying a 2000 GS300. It needed tires soon so I decided to just get 18" tires and rims. The car had a slight shake at highway speed before but I'd just assumed it was because of the worn tires. Anyway I put new 18's on the car and it had a shake around 75mph and it gets worse as you go faster. I took it in and had the tires/rims road force balanced and one was out of spec so I replaced it and still it vibrates. So next I get hubcentric spacers and that did seem to help but it was still there. I was so mad that I bought 4 brand new Nitto 555R's last night and it didn't help a bit either. The car is stock ride height with 78K miles. Where do I go from here?

Neo

iTrader: (3)

How long has it been since the car got an alignment?

clubfoot

Is the shake in the steering wheel or car body?

marksexton

I'll have to look through the service records that came with the car, but I was about to do Eibach springs and get it done again anyway.

The steering wheel shakes some, but I can feel it throughout the whole car. What's strange is at 80mph cruising the car will be perfectly smooth for say 1/8th mile, then the next 1/8th mile it'll have a shake, then it's smooth again, and on and on and on.

E-Z ES300

Definitly not a alignment or maybe most likely not, the only way to tell if she needs an alignment is when your going in a straight line the car turns to another lane, shaky at high speeds means you need the wheels balanced

marksexton

The tires have been road force balanced and all are in great shape and run out on the wheels is excellent.

GSteg

iTrader: (15)

Does it only happen at high speeds?

Have to checked to see if your rotors are warped?

Have you checked the balljoint/tie rods?

FrankWhite

same thing for me exactly...when stock 16s on no vibration...when 18s are on vibration around 75

tmf2004

iTrader: (15)

Don't forget to check tire pressure,torque specs to 76, rotors and pads...

FrankWhite

specs to 76? whats that

fbapacible

your lug nuts.

clubfoot

If the entire body is shaking then it is drive train related, i.e. drive shafts, center support bearings, CVs, trans & engine mounts, sub frame mounts, etc. Make sure that when you balance the wheels and tires you do it hub centric as well. How much mileage on the car?

1) try it again without over drive engaged or in one gear lower than top gear.
2) check engine mounted accessories for security.
3) check front and rear suspension for looseness.
4) check shock absorbers.

Kbueno

Most likely worn Bushings.

sockfocks

iTrader: (1)

I'm with this guy..check the caster arm bushings and lower ball joints...

marksexton

Thanks guys, the car has 77K miles.