VSsc400

iTrader: (1)

what made you change them?

did you experience any symptoms before changing them?

did it resolve the problems that you had?

I have some vibration issues from 65mph to 80mph...

1. I replaced the tranny mount
2. inspected motor mounts and they are good as new
3. tightened sway bar and endlinks
4. car has complete set of Daizen Bushings
5. Checked height on all 4 corners of coilover. Adjusted RR lower by 1/2 mm and Adjusted FR higher by 1/2mm
6. Alighned the vehicle 2 times
7. new tires and rotated them 2 times
8. balanced tired 2 times using hunter load bearing balancer
9. Checked wheels for trueness
10. Checked all exhaust mounts and they are good
11. Full tranny flush with Toyota type IV and T-Tech tranny service machine.
12. All new hub centering rings
12. new lug nuts.

The only thing I can think of that I have not done is the steering rack bushings...
or
Wheel bearings, but they seems good (using the "jack up the car and try to shake the wheels.

Any input would be greatly appreciated
Car is a 92 SC400 with 106k miles

dennis

VSsc400

iTrader: (1)

posted in wrong forum.


moving to suspension section.

siniquezu

haha...you moved your own thread.

aasc300

I heard that when the steering rach bushings go bad you get slop in the steering. I havent heard of it causing a vibration, but if the rack is wobbling left to right while driving, it could cause that vibration. Try turning your wheel left to right and see if there is any delay before the actual wheels turn.
Good luck and let me know what you find.

verylost

It could be that the Daizen bushings have degraded after a year. There were a few people in the suspension forum saying that the bushings didn't hold up after a year. If I recall correctly, we had a pretty rough year with snow in NY, and the above normal amount of salts and other crap on the road could have done significant damage.

djl

Inspect the center support bearing on the driveshaft, they always fail on high milage/age SC's. These bearing are encapsulated in rubber and develop excess slop/play over time just like suspension bushings.

Good luck.

setwire

I had my motor mounts inspected by a very good mechanic.
He said they were OK.
I ordered replacements anyway.
When the motor mounts were removed for replacement they were both very bad,
If you have 100,000 miles on your SC then you probably need new motor mounts.
They look OK until you remove them.

Rob

VSsc400

iTrader: (1)

verylost: my car was stored over the winter. The symptoms started when I left for my california trip just 2 months ago. I also went through every bushing on the car with the wheels off and on jacks and inspected all the bushings one by one.

djl: i will look into this

setwire: the motor mounts and the tranny mounts were changed only 46k miles ago. The tranny mount when i removed it was still very good condition.

setwire

VSsc400
What is the mileage on your car?
Steering Rack bushings are not even listed as a part in the Lexus Parts CD.
Vlamos in Aus has them available for $50 Aus and he is as far as I know the only person on the planet that has them available.
I replaced mine when I ordered all of the control arm bushings from him.
My car had 96.000 miles on it when I did all of this and the steering arm bushing were pretty soft and were definitely on there way out.

Post the mileage on your vehicle, it is a good indication of what condition they will be in.
I live in Vancouver, Canada, your location has a lot to do with what condition all the rubber on your car will be in.
Just remember the condition of your motor mounts is very difficult to ascertain until they are removed.
Mine looked fine until they were removed.
The right motor mount was totally detached and the left well on its way .
Visual inspection tells you almost nothing, the total mileage on your vehicle is the indication of the condition of your mounts.
After I replaced motor mounts, trans mount and all the control arm bushings my car now feels and handles better than the newer Lexus cars.
Rob

setwire

VSsc400

Can you be a little more specific describing the vibrations you are experiencing?
Are the vibrations in the car as a whole or just in your steering wheel?
They could be caused by many things.
A wheel balance weight lost can cause this problem?
Perhaps this could be your problem.
A lost wheel weight on one of your front wheels could cause this.
Rear wheel balance is not as noticeable but could also be the problem.

Rob

VSsc400

iTrader: (1)

I bought the steering rack bushings and will be installing them very roon.

car has 106k miles
motor mounts and tranny moun changed at 60k miles
I have all the wheel weights still on and intact.
Vibrationis can be felt throughout the car. The whole car shakes.

thank you

RTLEXSC

Check driveshaft and make sure you don't have a bent wheel.

bmatsu

Did you have to remove the driveshaft on any of your fixes?
If so make sure the bolts on the driveshaft, especially on the diff side are tight.
I changed my clutch, developed a vibration and that was the problem.

Hope this helps

setwire

bmatsu

I had the same problem with loose nut on my SC400.
Lexus dealer told me i needed a new drive shaft, bearing and new differential.
It turned out to be a loose nut in the trans shaft.
My mechanic tightened the nut, applied locktite and have not had any vibrations since.
I did change out my torque convertor for a dragon unit and changed the trans fluidfrom Dexron II to Toyoto Type IV fluid which I believe was causing some of the shuttering in my trans.

My car now is as smooth as a New Lexus off the showroom floor.

The type of trans fluid has a lot to do with vibration problems.

Rob

Bryan858

iTrader: (1)

Hey VS, did the bushings work out for you? I think I have a similar problem..... Did you do the install yourself? What was involved in doing it? Hope to hear from you... Bryan