Bteljuice

I got a warning that i still have 500km to go for the front brake pads.

How do I know if I need to change the sensor and rotor?

I do get slight vibrations when I brake (I have OEM wheels, brand new Michelin tires, wheel balancing and wheel alignment last week).

The mechanic told me it is either the pads or the rotor.

Rotor is quite expansive, so if it is not necessary to change, I would rather not to.

EDIT: I have 80,000km = 50,000miles on the odo and never changed my Rotor

acuteperformance

Hi,

Your BMW should have a brake sensor, when you need to change your pads the light will come on telling you to change them. How many miles do you have on your rotors? Is the vibration only apparent when you brake? If so, you could have a warped rotor. You could always go aftermarket. For example:

Hawk HPS Pads
Front - $100
Rear - $75

Posi Quiet Pads
Front - $60
Rear - $40

Rotors
Front - $175
Rear - $160

It's the shipping to where you are that will be more expensive.

Michael
Acute Performance

acuteperformance

http://www.ehow.com/video_2328349_as...otor-wear.html

Bteljuice

Thank you Michael.

Yes, I only get vibration when I brake. Unfortunately, I WISH I CAN GO AFTERMARKET. I am currently in the Middle east(where my car is), so shipping will take time and money, and I need to change them ASAP since I am traveling back to Canada in 4 days.

And I am mostly worried that if I change the pads now and when they are broken in, I would find out that I have a bad rotor which will damage my pads, so you see my dilemma.

Defy

Sometimes you can get your rotors turned depending on how warped but i would always just upgrade!

mookish

I am from the camp that says with BMW, change pads and rotors together.

Cal@Jlevi SW

I would have a certified BMW mechanic inspect the rotors to see how bad it is, and if resurfacing is an option.

AlwynMike

It sounds like your rotors (discs) will need changing.
As has been said, you can get them resurfaced, but BMW discs are very tight on allowable thickness. I had to change my discs at 40000 miles as they were below the thickness limit - and I don't use the brakes hard, and my car is a manual, which does not need as much braking power (there is no engine braking from an Automatic).

There is an easy way to check your discs. Any good mechanic will be able to do this, and have done it before.
The proper way to do it is with a dial gauge, which bears on the disc - turn the disc slowly, and the dial gauge will indicate the run-out.
The alternative way is to place something very close to the disc - I usually use a wheel nut spider as I use one to remove the wheel anyway. As you turn the disc, you can see the run-out. I don't know what the limit is on your car, but much more than a few thousandths of an inch is too much - hence the need for getting the spider (or whatever) very close. If there is some run-out, you will also hear the tool rub on the disc in the place it is warped.

Mike

inktoxicated

if u gonna drop dough buy a after market big brake kit

Bteljuice

Thank you everyone for your input.

I have a 520i, so there is no need to upgrade to a BIG brake kit.

I am taking my car tomorrow morning to the mechanic. Hopefully he will tell me what to do. In all cases, I already bought the sensor and the pads from BMW