New Brake thickness?

  • Thread starter Thread starter Zed
  • Start date Start date
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Zed

My Hyundai multi point inspection report says that disc brakes need to
be changed at 3mm or less and drum brakes need to be changed at 1mm or
less.
I am wondering how many millimeters thick the pads and shoes are when
they are new for an '03 Accent?
 
Zed said:
My Hyundai multi point inspection report says that disc brakes need to
be changed at 3mm or less and drum brakes need to be changed at 1mm or
less.
I am wondering how many millimeters thick the pads and shoes are when
they are new for an '03 Accent?
Click to expand...

The front pad recommendation is BS. They start out at ~6mm, so they're
telling you to change them at just over half their life. Changing at 1mm
is fine at both ends.
 
i do not know there you bought your pads but mine were a good 10 mm (3/8")
thick.
It is a good idea to change your pads at 3 mm 1/8" because it stop your
disks from over heating and warping.
use all the pad and you need a disk job, use a little less and not disk work
required.

FINN
 
Finn said:
i do not know there you bought your pads but mine were a good 10 mm (3/8")
thick.
Click to expand...

Come to think of it, I probably underestimated the thickness of the pads.
It is a good idea to change your pads at 3 mm 1/8" because it stop your
disks from over heating and warping.
Click to expand...

How so? The amount of heat the rotor sees is the same, regardless of the
thickness of the brake pads. The caliper pistons may see slightly higher
temps with thin pads, but not enough to make any difference.
use all the pad and you need a disk job, use a little less and not disk work
required.
Click to expand...

That's only true if you let the pads wear to the point that the metal
backing plate makes contact with the rotors. As long as there is
friction material left, no harm can come to the rotors. 1mm is plenty of
material.
 
One caveat that I forgot to mention is that brake pads rarely wear at
the same rate, so you must check all four of them and replace them when
the thinnest one reaches the minimum thickness. I suspect that this "old
mechanic's tale" of changing at 3mm of pad material left is probably a
hedge against uneven wear.
 
2/32" is the industry standard for minimum brake thickness. This converts
to about 1.6mm. 3mm is significantly before replacement is necessary, but
you should also consider that you may be below minimum prior to your next
3k service.

Pad thickness does not affect the amount of heat transferred to the
rotors. Braking systems are very efficient, and, if I recall the figure
correctly, convert about 99% of a vehicle's kinetic energy to heat. In
other words, the amount of heat resulting from a stop is dependent solely
upon your vehicle's mass, speed, and rotational inertia.
 
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