I have a situation which s been going on for long time and it only gets worse. Couple of mechanics seen it and i trust my guy however no solution:
While driving downhill if you apply brakes, the car doesnt really shake strong until you press the pedal stronger but there is loud noise and brakes dont perform well. If you press the pedal tougher it will get super loud. This sound is hard to explain but what i can tell you is: when washing machine comes close to the end rolling like mad cow, sometimes machine starts to move and you hear this crazy noise its similar to that. The worst part of it is that the brakes dont hold well when this happens. Especially when you need to come close to a stop car shakes like a tiger tank and brake performance gets worse at least 2-3x than standard ( nothing felt on pedal or steeering)
It happens when you are a bit faster if you do more than 40 mph , you get faster it gets worse.
I know that you shouldnt brake while going downhill fast but i live in a place where we have many small mountains and intercity road so its unavoidable.
I have changed everything and no help: pads and rotors, rear left caliper was sticking along with blocked brake line, both were changed. Brake fluid changed. None of them helped.
Check the suspension bushings. Especially the ones that keep the wheels from moving front to back.
A bad bushing will allow a resonant vibration to occur under braking like a warped rotor. That vibration may cause the wheel to hop reducing the effectiveness of the brakes.
Also take a good look at the engine mountings for the same reasons.
If you have ABS, pull the fuse and test brakes. Find a safe place and do it slowly at first. Before that, have someone step on the brake and watch the brake booster and listen to it. If you hear it leaking or it moves around there may be a problem with it. That never works but I’m looking for something odd. Broken strut? As always; get rid of it before it gets rid of you.
thanks everyone for the comments! funny thing, after i wrote when i started to drive today, after 3 years now it started to happen on low speeds and straight road. I also started to hear this noise while driving (brake pedal not pressed) but not loud.
First thing, I will remove the fuse, I couldnt locate the correct one as the paper on the fusebox doesnt show abs. Need to find the book at home and check/find correct one.
But after what happened today it feels more like issue with brake system or suspension. However, definitely it became dangerous to drive now, before today I was driving slow in general when I was going downhill.
Biggest problem while going to mechanic with the issue was, they could not replicate it, I also have been to authorized dealer on this but no avail. Now, they will be able to replicate as well
definitely did not buy OEM :D, oem parts are crazily expensive.To be honest I didnt really check/compare the specs versus OEM. I fitted with a recommended brand (cant remember right now probably Bosch or Brembo, it was more than 2 years ago). However, we guessed with the mechanic that the previous rotors were originals and the problem was there after I bought (before I changed anything)
One very easy thing to check on the lower rear control arm “pancake” bushing, one can do from in the car using you or a friend to visually watch each front tire for forward/rearward movement within the fender well (not rotational), there should be very little to no movement under lite acceleration/braking, only needs to be a foot or so, can preform this in a typical home garage…
One of the neighbors have straight yard and more tools than me, so 2 days ago we came together to lift the car.
Before thay removed abs fuses, still no avail.
What we found out like one of our fellas said above, rear control arm was in bad cond.ition
Second thing, while checking brakes we recognized also front right one probably seizes. While turning the wheel with hands, it drags. After looking at the caliper, the seals were visibly worn.
For this one, you think aftermarket caliper or regeneration of the caliper is better idea for a longer solution? We didnt do anything yet, will order parts and probably next week we ll fix but i couldnt decide on the caliper.
Not sure if these would solve my issue but we will see.
Note: both of us are very ameteur while he s much better than me , about fixing cars. So i wouldnt trust on us for regenerating it properly. If recommended then i can use the mechanic for it.
Calipers are cheap insurance for stopping your vehicle in times of need, nothing like finding out you did it wrong in that time of need, remember, if your brakes don’t stop you correctly, something else will…
Buy new or reman semi loaded or loaded calipers only, and always in pairs, when they have much wear on them (over 12 months and 12K miles), as mixing hydraulics can cause pulling issues…
Semi loaded calipers come with all new hardware as well caliper brackets, the slide bolts can be seized in the calipers causing uneven wear and unproportioned braking…
Something else to consider, replace both front brake hoses while they are already detached from the calipers and you are having to bleed the brakes anyway.
Is the drag consistent? If the brake appears to drag, release, then drag as you rotate the rotor, there is excessive rotor runout, a warped rotor, excessive rust on the hub or a bent hub.
Brake pulsation and/or vibration is generally caused by warped rotors, not ABS malfunctions.
