fjstl

this car has 150000 miles and while while driving this week, I experienced severe rear vibration. I thought I had a flat tire and checked it; turned out that the rear snow tires were fine. I then proceded to about 65mph, when the vibration occurred again. I then droved it to the Lexus dealership. They said I needed to have the rear brakes replaced - a lot of rust and pads wearing unevenly. They replaced rotors, pads, and shims. Drove the car 10 miles and the vibration occurred again. I returned to the dealership and they balanced all 4 tires. The mechanic said that the snow tires, which are General Altimax Arctic, are a softer compound and when driven fast could cause the tire to come out of balance for a few minutes. I then brought the car to where I purchased the tires, and they said the tires are fine. Tonight, while driving about 20 mph, the vibration occurred and did not end until after about 5 minutes, when I stopped for a few moments. The trani seems fine, but the vibration continues even after taking my foot off the gas pedal.

Has anyone experienced this or have a solution. The dealership is clueless.

amcdonal86

Does it seem to be related to the drivetrain? I know you said that the vibration continues even after taking your foot off the gas pedal. Is the vibration related to vehicle speed?

I wonder if your driveshaft is out of balance, or your differential mounts are shot?

fjstl

it could be the drive train and I was leaning in that direction. The problem is that it is not a constant. It comes and goes. My next step is to being the car to my independant mechanic. thanks for the response.

amcdonal86

Is there any sort of whirring noise that is associated with it? Or any noise of any kind?

I would have him check any sort of engine mount, transmission mount, or differential mount, and bushings your rear suspension. I've not heard of many issues with the rear suspension, though.

fjstl

there's no noise of any kind other than the vibration. thx.

Jrezo

This is what happened to mine. Cheap and easy fix if your up for a quick DIY

https://www.clublexus.com/forums/ls4...ans-mount.html

JimsGX

Do you use the emergency brake at all? Did they replace the rear rotors? Did they do any work on the rear drum brakes / emergency brake components? The inconsistency of it is a but puzzling. If you tend to use the e-brake, my thought is that it could be not releasing completely sometimes afterwards.

fjstl

they replaced rotors, pads, shims and also worked onthe ebrake. what they did, did nothing to resolve my problem.

amcdonal86

My guess is it's the transmission mount.

fjstl

the trani mounts and rear components check out to be ok. It's beginning to look like a brake calipre may be hanging up intermittently. Still checking.
thx for the replies.

amcdonal86

I think you should look at the e-brake like someone mentioned. My brakes are perfectly smooth, but if I engage the e-brake while at speed, there is an intense vibration that comes from the rear.

Try engaging the e-brake while driving at 20 mph or so and see if it produces the same vibration you experienced earlier.

fjstl

it's back at the dealership and I brought up some of the suggestions from this site. Hopefully they can figure it out. thanks.

fjstl

as it turns out, according to the dealership, the ebrake components have to be replaced - at their cost - since they are causing havoc with the calipre. I hope this resolves the problem.

amcdonal86

Sounds good. Hope it gets fixed soon!

fjstl

me too. thx.