Brake Vibration At High Speed And Loss Of Power

[luchlexus]

Greetings,

I'm a newbie and joined this forum to see if someone is experiencing a similar issue that I am having on my 2004, rx330 with 28k miles. After reading through the various strings, i've found similar complaints with slight differences so posting a new one. When traveling at high speeds and applying the brakes lightly, on rare ocassion i experience sever brake vibration or juddering. The added complication is that when this vibration happens, it also translates into vehicle vibration and then a loss of power (like press on the gas and nothing really happens). Once I slow down or come to a stop, all returns to normal. I've had the vehicle in to the dealer for several issues and they cannot repeat this which sounds like a 'standard response'. Is there a reason why brake juddering at high speed could also translate into loss of power? Note this does not happen often but when it does, it's frightening and the braking power is severly reduced, hence i'm very concerned since my wife drives around with my 2 year old in this vehicle. Any suggestions?

[bngu1]

exact same thing happened to my 04 RX. took it for the dealer to look at it. they replaced the front rotors and pads under warranty.

[Grumpa72]

This definetly sounds like a warped rotor or two. Have you asked them to put a dial indicator and check the runout of the rotor? If you can't duplicate this, then a physical examination of the rotors using the dial indicator willl almost certainly tell you if the rotor is the issue. I would do this while it is cold and then after driving the car. The loss of power is confusing but I will go out on a limb and suggest that perhaps a brake is dragging because a caliper is not releasing? If that is the case, you can sometimes tell by putting your hand on the axle hub at each wheel and see if one is unusually warm. Obviously, the car must be driven to get sufficiant heat build up to check this out. If your shuddering happens again, continue to drive the car for a few miles and then find a safe place to pull over. Then you can check each hub for excess heat.

Gary

[grataballi]

We had the same thing happen to our 2002 RX300 - the indicator was that when braking on a hill, you'd feel the slight pulsing, but nothing major. At speed (60+ MPH), especially on the freeway, when you have the occasional sudden slowdown, and pushed the pedal pretty hard, the front would shake violently.

All it turned out to be was warped rotors. Had them turned for $10 each at a local shop - used the same pads (since they were 60% there), all was good.