VSsc400

iTrader: (1)

I'm starting to experience somewhat noticeable vibration from on my 92 SC400.

Facts
vibration @ around 65mph-70mph (+ - 3mph)
No vibration at any other speed.
Shifting is smooth all across the gears.
The vibration is not there when I accelerate through that speed range but is only there when I am cruising at those speeds.
Weather I am turning or going straight the vibration is there.

Recent service
New 18" Wheels & Tires balanced and aligned 5k or less
Full Tranny service 5k or less (type IV toyota)
Lexus dealer oil change 2k or less
radiator service 5k or less (lexus red radiator fluid)
differential service 5k or less
fuel injection service 5k or less
fuel filter 5k or less

Any help or suggestion would be appreciated.

Thank You

Dennis

pcmw

VSsc400,

The vibration at a set speed range is usually the wheel balance, or flat spot on the tires (cupping).

Being that you have nice wheels, and tires, I would think it is possible you bent a rim on a big bump or they lost a weight or two while spinning. Get them checked at the place who installed them. If a wheel is off, ask them to remove ALL the weights and re-balance the wheel. While the wheel is off the car, measure tread depth in 3-5 places with a guage that the tire store should have on hand. This should tell you if they are wearing evenly.

MW

VSsc400

iTrader: (1)

thank you for the good info. I will have that done and post back the results. One thing that still boggles me is, why would it happen at that speed and not other speeds?

gr8j123

i know exactly what the problem is...had it on a gs400...your brand of tires would be the problem...certain brands make a difference...if you take it to lexus...they will tell you that it is something wrong with the steering column...but nope, its the tires. since you recently upgraded tires that sounds like the problem. but i could be wrong...worth a shot to swap tires and try...

JohnnySC

I am willing to bet it is the tires/wheels also. My GS430 rims came off my mom's car and I have the same problem. She only had 2k on the car when I took her wheels (dad upgraded). Anyways, at highway speeds over 70mph, the car vibrates and I can feel it through the steering wheel. My problem is, one of the rims was improperly balanced as a result of losing a sticker weight. Go to the tire shop and have them computer balance your tires and wheels, it will make a difference.

djl

Most likely you are hitting a resonate frequency due to poorly balanced tires. Tire balancing equipment are not creatly equally, and most shops do not spend for the more accurate models. Go to gsp9700.com and find a local shop with a Hunter GSP9700 balancer, they are the best, period.

Good luck,

DJL

kylesc400

would the tires have anything to do with the 40-ish mph vibration/rumble that is fairly common? i recently had my transmission fluid changed and it didnt make any difference, i still get the rumble at about 38-41mph, but no other speeds. i feel it when accelerating past that, decelerating thru it, or just holding that speed (its constant then).

Bentley1

I am in agreement that it is most likely your tires. I hid a similar problem that I finally gave up on after 2 years. Eventually the tires wore out (Dunlop), so I replaced them with some nice Michelins. Problem solved. Smooth as glass now.

skpark70

iTrader: (1)

[QUOTE]Originally posted by VSsc400

Facts
vibration @ around 65mph-70mph (+ - 3mph)
No vibration at any other speed.
Shifting is smooth all across the gears.
The vibration is not there when I accelerate through that speed range but is only there when I am cruising at those speeds.
Weather I am turning or going straight the vibration is there.

You Know I have the same problem with my 97 SC300, and discovered that my rims(17s) were bent and then i've purchased some new rims(18s) but still having the same problem, I also had them balance twice. And far as tire goes, previously had Yokohamas and now I have Michellins. I'm due for service soon and hopely solve the problem.