gtg302s

I have searched other threads on this forum and have not yet come across the solution for this perplexing issue with our 99 ES300. Please forgive me if this ends up being a common issue that has already been addressed. This is my first post.

The issue: When driving at a high rate of speed on the highway (60+ mph) and needing to brake for traffic or anything else (whether or not I come to a complete stop), the steering wheel will begin to slightly shake after I finish braking and am again driving. As I am driving, the shaking will gradually get worse. The shaking is much more violent as I brake to come to a stop. It gets so bad that I am sometimes forced to pull over.

The temporary fix: I found that if I engage the emergency brake and then disengage, the problem is fixed until I need to brake while driving at a high rate of speed again.

Already tried to fix: When getting my brake pads replaced, my mechanic told me that the front drivers side brake pad was almost completely gone and my front passenger side brake pad looked new. He told me to replace the front driver's side caliper because he thought it was sticking. I replaced that caliper and had new brake pads installed, but the problem remained. I had my tire/brake shop look at it (after telling them that the e-brake trick temporarily fixes it) and they said that there was a spring and a piece of hardware missing on the rear passenger side for the e-brake gear. I had this replaced and the problem remains. The tires are in good shape. I've tried rotating/balancing and that didn't fix it either.

I am not sure what else to check. I can try to take the car to different shops and see what they have to say. It's perplexing that engaging the emergency brake and then disengaging it fixes the problem and allows me to drive on the highway again without the shaking (until I have to brake again). I am very hesitant to take this vehicle on road trips because I need to pull over and perform the e-brake trick to get the car to drive correctly. Overall, it feels like I'm driving with the brake on when the problem is occurring. The problem and temporary fix are easily reproducible. I simply try not to brake while driving on the highway and know that if I do, I'll need to find a place to pull off soon to engage and then disengage my e-brake before continuing with my trip.

Thank you for any information you might be able to provide!

hypervish

Welcome to Club Lexus!

The shaking while braking seems to indicate that the rotors are warped.

BTW: you probably didn't need to replace the caliper, you could have gotten away by just lubing the slide pins.

gtg302s

After braking at high speeds, the shaking begins and continues to get worse even when I am not braking. It does get much worse when I stop though. Since it is shaking even without braking, it appears to me that there is something going on other than rotors. Could it be that slide pins need to be lubed because maybe they're getting stuck after the initial braking at high speeds? Could engaging the emergency brake and then disengaging it be forcing the pins back where they belong? That is what a friend suggested. Would the emergency brake affect all 4 wheels or just the rear ones on this model?

gtg302s

Thank you for your response by the way!

dinkel41

jack up the car in the front grab the tire bottom and top see if it will wigle if does you need hub bearing.

hypervish

You're welcome!

It's possible that the slide pins could do that. It doesn't hurt to lube them. They should be cleaned and lubricated every 2 years.

The emergency brake only affects the rear wheels.

bighenny

I am having a similar problem. What was the cause?

LeX2K

The person never came back to tell us.

arthurb999

I had the same issue... got a full break job (pads, rotors, front calipers- which i know i needed) and did an oil change, tire rotation, and 4 wheel alignment. That fixed it and it ran great!