WaryDriver

I'm new to brakes. The "service limit" is "1.6 mm". Do I measure the pink distance (see pic below) for this limit? Or is it the yellow distance to the outer metal shim? Or is it the red distance? How much estimated life do these pads have for normal driving? Also how do i keep my rotors from rusting since I dont drive my car much?

ezone

Rust is natural, you can't stop it.



You locate and measure the THINNEST pad out of the set.
You measure the amount of useable pad material.
The steel backing plate is not friction material.
The shims are not useable material.


That would be your pink arrow.
But only the thinnest pad counts.
I see roughly 4mm there. That's around 25-50% remaining, depending on how you want to measure.
You have plenty of time left.
Look at the other side too.
The inboard pad usually wears a little faster than the outboard pad.
They can wear at an angle too, so you may need to lift the caliper up to find the thinnest points of the pads.

If you live in the rust belt and the car sits a lot, you may want to remove the pads and check for bonding problems.
And rust causing the pads to bind in the brackets.

The 1.6mm is the point where the wear indicator (the squealer) starts touching the rotor.


New pads are maybe 8-10 mm thick.
Wear limit is roughly 1-2mm.
Soooo many people have no clue what the wear indicator noise is.
(You do NOT want to run pads to zero, you start buying rotors at that point.)