brake issues!!!!!

[houay2005]

hi. ive been having alot of issues with my brakes. the brakes keeps pulsating or shaking the car as i press on the brake pedal. i already changed the front rotors and brake pads 6 months ago. NEW. it was doing this a year ago and i changed it but now its the same issue. i was told by a friend it may be a warped roter and i needed to get it resurfaced. or that it could be my bolts arnt tight enough or that i bought the cheapest brands. im going to go with the drilled sloted rotors for my next change up. any suggestions on my problem?

 

[pgarner]

id advise against the drilled discs as these are normally weaker and more prone to cracking than solid ones

do you work the brakes hard ?


(moved to technical section)

 

[HDi fun]

You could be experiencing what's called Pad Material Transfer. When you have come to rest, release the brake pedal - don't keep it pressed down.

 

[indiaman]

Check the brake disc for runout, even a small amount of runout will cause judder and pedal pulsation. also, if you have ABS, check operation, as defective ABS is known to cause pedal pulsation

 

[houay2005]

i try no to work the brakes hard. i do keep the brake pedal pressed down even if i have stopped. if not then the car will move forward.
yes my abs light is lit up. i was going to get it diagnosed today to see whats wrong. i think the recent owner had the wire unpluged because i had a issue with the cluster gauge not lighting up (issue in another forum)and noticed a bunch of wires not pluged in to where the abs light was located. it must of been lit up for a long time now. i thought the drilled hole rotors were better cause they cool the rotor faster? at least thats what they said? iono hit me back asap thanks!!!

 

[pgarner]

i try no to work the brakes hard. i do keep the brake pedal pressed down even if i have stopped. if not then the car will move forward.
yes my abs light is lit up. i was going to get it diagnosed today to see whats wrong. i think the recent owner had the wire unpluged because i had a issue with the cluster gauge not lighting up (issue in another forum)and noticed a bunch of wires not pluged in to where the abs light was located. it must of been lit up for a long time now. i thought the drilled hole rotors were better cause they cool the rotor faster? at least thats what they said? iono hit me back asap thanks!!!

DONT hold the pedal down hard when stopped. if the pads discs are hot then, as hdi said, you will have material transfer from the pad onto the disc. also holding the pedal down hard can, supposedly, cause damage to the master cylinder.
abs could be the problem if it cant see the speed from the wheels.

drilled discs are more for weight than cooling

 

[HDi fun]

If the car is automatic then apply parking brake and select N if stationary for any amount of time.

 

[houay2005]

pgarner you said drilled disk is more for weight? please explain.

 

[HDi fun]

PG is saying that drilled discs are use to reduce unsprung mass as opposed to enhance cooling of the discs.

 

[pgarner]

cheers Hdi thats exactly it.

go pick up a 330mm vented, but ungrooved or drilled, disc and feel the weight of it (my 312mm are around 10kgs each) drilling out some of the metal means that they become lighter. however they lose some structural form and more prone to cracking

 

[HDi fun]

Alloy wheels also help dissipate heat effectively. Not because of the airflow so much but because of the fact that aluminium is a superb conductor of heat. Bolting a big chunk of it to the hub lets the entire road wheel act as heat exchanger.

 

[old-git]

Drilling (if done properly) also helps to remove brake dust.

 

[HDi fun]

Drilling (if done properly) also helps to remove brake dust.

And send it where?

I think that drilling is more likely to be useful in removing the polished surface from a pad that's underused. This will create dust.

 

[indiaman]

Drilling (if done properly) also helps to remove brake dust.

I read somewhere years ago (road & Track I think) that drilling a brake rotor was done for two reasons, to allow water to drain off faster during wet weather, and to get rid of the gases caused by heavy braking which otherwise would form a boundary layer.