maverick02

Hey guys, I just rotated my tires and checked the rear pads and they appear a bit low, so I guess i'll have to replace them soon (first time). I just use the rx8 as a daily driver.. don't need anything special.. should I replace them with the stock pads or go with an aftermarket one that are just as good for less money?

Also, as far as I can recall, I don't notice any vibrations when braking.. should I still have the rear rotors resurfaced?

Thanks.

kingaaron

iTrader: (1)

Just replace the rear with stock pads since its a daily driver.

ArXate

I agree with kingaaron. Stay with the stock pads. No need to resurface the rear rotors. BTW, I have over 150,000 miles on my 2004 RX8 and I'm on my 4th set of front pads (i.e., replaced 3 times) and 2nd set of rear pads (replaced 1 time). I've stayed with stock pads. Never resurfaced the rotors, not even the front rotors. In general, no vibrations. Bleeded my brake lines once.

Don't listen to Mazda techs or other mechanics, who just want to help their industry make more money. Don't need to resurface until there are vibrations.

maverick02

Wow... 150K on the front rotors and they're still good? I would've thought at 150k, the rotors would have the thickness of aluminum foil heh :P

ArXate

That's what I had thought as well. But I slapped on the last set of front pads on recently at about 145,000 miles, and everything worked great. In fact, I didn't even bed my pads in and there's virtually no vibration at any time. The set before, I followed a bedding procedure from online and sometimes it would vibrate a little.

FYI, each of my front brake pads lasted 44,000 to 49,000 miles.

kingaaron

iTrader: (1)

My first set of pads lasted 50k, I expect this set to last about the same amount of miles since its a daily driver.

Nubo

The shop manual has specifications for determining whether or not the rotor needs to be resurfaced, and whether or not it *can* safely be resurfaced. They are simple measurements.

TrochoidMagic

^^

what nubo said. but a minimum thickness is stamped on the rotors, and a tech won't cut the rotors if its within that range.

its as simple as putting a micrometer to it. and as cutting the rotors during a brake job is simply to make sure the rotors are true when new pads are installed. because sometimes... just sometimes a backyard diy will put on new pads when rotors are too thin, and rotor warping sets in and kills the new pads with it.

Nubo

And also if the rotor is grooved too deeply or worn too unevenly, the new pads will not contact the rotor over a sufficient area, leading to poor braking, and also the points that do contact will generate excessive localized heat. This is even if the rotor material is sufficient thickness. Pads will "wear in", but it's a matter of degree.

hornbm

iTrader: (1)

You should always cut the rotor when doing a brake job if you have the ability.

ArXate

There are plenty of people who disagree.

swoope

iTrader: (5)

put new pads on the rear and it will be fine.

if you wonder do the measurements yourself..

btw, you owe me 18 bucks!

just saying..

beers

nycgps

iTrader: (1)

I have about 54K on original Rotor, and 4th set of pads (2 replaced from TSB, and I just replaced it myself not long ago)

Im going to replace the rotor on next set of new pads.

Why cheap on Rotors ? I mean seriously.

maverick02

Hey guys, when you slap on new pads using the existing rotor, do you still bed-in the pads? What about old brake pad residue still being on the rotor?

Nubo

I put some miles on them first so that the and rotors mate (take the same shape). Otherwise, some spots contact first and you won't really be laying down a consistent layer of transfer material and the heating will be uneven. If the rotors were resurfaced the break-in period won't be too long. If you replaced the pads without resurfacing it will take longer.

And again, I'd reiterate that the decision on whether resurfacing is needed should be driven by the specifications set forth by Mazda. It's just as silly to say that rotors never need resurfacing as it is to say that they always need resurfacing. Some do, some dont. You find out by measuring things such as runout, thickness, and depth of grooves.

swoope

iTrader: (5)

not really an issue unless you are using an odd compound made for the track, and using them to the extremes the track brings..

btw, no bite on the you owe me 18 bucks comment. i am shocked..

beers

maverick02

I'd like to measure the runout, but I'd really prefer not to spend 50+ bucks on a dial indicator right now.. If there aren't any vibrations with the current pads, couldn't I safely assume that the runout is within spec?

ArXate

Bingo. You're thinking exactly how I think now. Slap the brake pads on and see how they work. If you have vibrations or a lot of squeal, then worry about the next step at that point, right? Don't make things more complicated than necessary, because believe me, I tend to do that myself. And even I have learned to relax a bit about the brake pad and brake rotor stuff.


In addition, aren't you changing the REAR brake pads for the FIRST time? As you know, the brake force distribution is biased way way way way in favor of the front brakes. In other words, the rear pads/rotors are used relatively lightly. So, I would imagine chances are very low that you'll experience anything weird with the rear brakes. Slap the rear pads on and go!

maverick02

Yeah, I'm aware the front pads do the majority of the braking.. I'm actually also asking these questions since I have to replace the front pads on my brother's `08 TSX, but I'm only receiving the pads for my 8 today, and for my brother, whenever Amazon feels like shipping out my order.. so I probably won't get to it for another week or so.