Brake Thumps and Pulsates
Asked by cheriwalker65 Sep 30, 2008 at 04:13 AM about the 1994 Lexus SC
Question type: Maintenance & Repair
My 94 SC300 has a pulsating thunk in the front right wheel that is felt in the brake when applied, and has gotten much worse. Does anyone know which part it is that needs replaced? Is it the Caliper? Rotor? or something else? The brakes still stop without scraping noises. but seem to be getting closer to the floor when stopping?
Thanks for all replies!!!!
6 Answers
may have to do a complete brake overhaul. rotors, pads, calipers may be seized, brake flush and an alignment wouldn't hurt.
I had the same problem with the Rx330. The ceramic brake pads generate so much heat, they worp the rotors.
Alright I see two problems...The pulsating and the reduced pedal response... Firstly the pulsating... Is the frequency proportional to the speed of the car? Or does it pulsate at a constant rate? Reduced pedal response isn't too uncommon as a vehicle ages. Small air bubbles work their way into the system, since gasses are more compressible than liquids this can cause reduced pedal response. This is generally solved by simply bleeding the system. There are other possible causes but air in the system is by far the most common. Lets try ans figure out the pulsing before you have anything done since many brake repairs require the brakes to be bled anyway.
People tend to think of their car like a person. It's ok until you think the car is going to fix itself when the brake starts squeaking. Well you let it go then the wheels start rattling. But you don't have time to see about it until.........Some lady on a cell phone pulls out in front of you and your pedal goes to the floor with a Oh **** scream and you realized $100 would have avoided all this 3 monthes ago.
bleed your brakes, if you cannot do it, please take it in its a safety issue!
pulse may be warped rotor. do you have old brake hoses because if they are expanding with pressure you need to replace them