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I'm replacing the pads and rotors.
Reason: Original rotors with 130,000km and some competition driving are probably due, and the current QFM HPX pads are hopeless on the track.
The pads have only been on for nearly 3 years/30,000km and, apart from normal/spirited driving, have only seen three (3) track days.

The front pads were evenly worn and have a bit over half the friction material remaining. About what I expected.

Rear pads are evenly worn with no taper. Right inner and outer have 5.5mm friction material - about what I expected, HOWEVER, the left outer has 3.2mm and the inner 2.8mm WTF??

I checked the previous pads - Remsas that were removed for the QFM - all four of those rears have normal wear and equal friction material.
I haven't noticed any noises apart from a bit of a rattle from the left rear on very rough surfaces which stops if the park brake is very lightly applied. No hot brake odours and no evidence of brake drag.

After fitting the new parts and seating the pads, both rears have about the same amount of drag with both wheels off the ground and brakes released. So, in the words of a well known political personality, please explain?

Haven't been able to test fly it and bed in the brakes yet as I am missing a front pad guide plate - the spring that retains the pad in the caliper. Lord knows why/where that's gone. If anyone in the Brissy area has one I'd be very grateful. Wreckers will only sell with a caliper and Mazda will only sell with a full set of front pads. I'll try Repco tomorrow and Automotive Plus om Monday.

Check and grease the caliper sliders and give it a full fluid flush

What he said.

Also, it might be a good idea to pull the calipers off, remove the pistons, and check that they and the bores are in good condition. Renew seals and boots when re-assembling.

Sliders are free and fluid was changed in February this year, April 2016 and March 2014 etc.

greenMachine wrote:Also, it might be a good idea to pull the calipers off, remove the pistons, and check that they and the bores are in good condition. Renew seals and boots when re-assembling.

Yeah, last resort. TFH for me to do with my facilities. I'll see how it is going in early December after bedding the pads, a couple of good drives and a track day.

I'm trying to figure out why it could be the left caliper piston. The piston retracted quite normally and has seated the pads after a few operations of the park brake. It locks up Ok and releases OK. Drag on both sides with brakes released "seems" the same.

JBT wrote:I'm trying to figure out why it could be the left caliper piston. The piston retracted quite normally and has seated the pads after a few operations of the park brake. It locks up Ok and releases OK. Drag on both sides with brakes released "seems" the same.

It may have been a sticking caliper or contamination on one side of the pad or disc. Clean the rotors both sides, do a lock up test to see if they lock up evenly, if they do them the problem has probably cleared itself.

All new rotors and pads now Custardtart, but I think you might be right about a possible temporary sticking caliper. Anyway, one of the PSCRAQ chaps in Brissy very kindly gave me a front caliper pad retainer spring (guide plate) he had in the spares bin so I could finish the job today.

I double checked park brake operation at the rear calipers with the car on stands and all was good.

Took it for a 40km test drive to bed in the pads/rotors and all good. Even transfer of friction material onto all the rotors, stopping dead straight, great pedal feel and no odours.

I'll just keep monitoring it now and check the pads again before and after track day next month.