Just got a 93 SC300 and have a question about slight vibration in the steering wheel and seat at 100 miles per hour -- the car has 81,000 miles on it. The shocks seem shot as I get a knock when I go over a small pothole, especially noticable in the rear. This is not a problem cruising on the highway though; I get the smooth, floating ride common to Toyota/Lexus. But at 100mph I begin to get a slight vibration that increases a bit as I get up to 110. Is this most likely the shocks or a drive shaft balance issue? I'm interested in improving the suspension and would appreciate any advice on this as well -- the best, easiest upgrade for the least cost -- would this be Eibach Kit, Tokico shocks, Daizen bushings? What's a ball park figure on this suspension and installation? Thanks for any feedback.

A couple other questions. Is the SC300 a good high-speed cruiser? Can it handle speeds of 90-100 mph for an hour or so; plus 80-90mph of all day highway driving? I do a lot of driving on desert freeways in Southern California & Arizona. Thanks again; this looks like a great forum

Newbie

 

This is the bushings...not the shocks. The shocks being worn will show leaking or will have little control of compression and rebound. Kinda like riding on a trampoline.

Sounds like a wheel balance / alignment issue.

Possible but not likely. An unbalanced drive shaft would tend to be more noticible at lower speeds and not really it in the steering wheel. More of a vibration under the shifter.

Please do a search on this topic. It has been covered time and time again. There is a great thread talking about a "full package". Searching is always a first move when looking for information on CL.

The car can handle the speed for hours. I drive from Sac to LA alot and the car will handle 100+ for long empty stretches of "test track" (of course, I would not condone or promote speeding in any way). The transmission tunnel on earlier models heats up a bit after 40mins. But the later models added more room in the tunnel from my understanding.

MW

 

I have to agree with PCMW that the knock from the rear is most probably worn bushes, could be upper/lower arm or sway bar, the sway bar bushes are easy to change and at that milage the car will benefit from having both front and rear sway bar bushes changed.

Another point is that any worn upper/lower arm bushes will throw out the steering angles, dont wait till they start knocking as the bushes can be completly shot long before they allow metal to metal noises, "on-car" inspection will not normally reveal bush wear, if you drop the arms you will find the rubber has perished and is allowing the arms to float around under load.

You dont normally get vibration from out of balance wheels over 80/85mph but is certainley a good move to have the tyres inspected for damage/seperation and balanced before proceeding onto other areas such as geometry or worn bushes (they go hand in hand).

I have driven my TT across northern France for hours at over 120mph, touching 150mph in some parts, never missed a beat, never feels strained, better than sex and it lasts longer although sex is probably cheaper as The Beast uses plenty of fuel at those speeds.

 

to be honest with you i have only had my baby up to 135...but she was smoother at 135 than at 90......


CEO

 

i have driven the car countless times from sf to la....and its an amazing cruiser

i have also taken few trips from sf to seattle with no problems


it easily handles 15 hour drives at 80-95mph

 

Can it handle speeds of 90-100 mph for an hour or so; plus 80-90mph of all day highway driving? I do a lot of driving on desert freeways in Southern California & Arizona. Thanks again; this looks like a great forum

Newbie [/B][/QUOTE]


I have driven my sc from the California bay area to south alabama back. 2350 miles each way @ an average speed of 100mph in 42 hours(each way) and no problems at all. in fact I think it runs smoother now than it did before hand.

 

I think that my car is smoother at 100 mph to 150 mph....than at say 50 mph or 60 mph....in fact i think it enjoys the 80 mph to 90 mph range...

 

I'd have to agree. mine doesn't seem to want to stay under 90mph funny thing.