1999Porsche911

The lip at the edge is normal and is a result of disc wear where the pads touch. And, yes, most dealers will try to sell you all sorts of services when they are not necessary. Like RMS replacement when there is no oil leak from the seal??????? Always verify any problems a dealer says exists.

PorschePRH

yep. that's the sort of tactic that forces you to no longer trust that person.

i just did all pad replacement, and i can tell you there is absolutely no shake whatsoever.

and there never has been when i do pad only replacement on many of my cars. i change a lot of pads because i always replace with low dust pads like EBC, ceramics, or in the 911 case, Mintex.

Tbred911

how do the mintex compare to OEM... are they as grippy? I don't mind the dust... I don't want brake squeal and at least OEM performance; are they cheaper than OEM pads?

TurboMark

Where to you buy the tool to measure the caliper thickness? Thx

PorschePRH

Mintex seem to have the same brake feel as stock. I don't know how much OEM's cost, but for all 4 wheels, Mintex was less than $100. There's no brake squeal. I wouldn't go for that either.

Calipers can be bought at any fine tool parts store. You can easily search the web for companies that will ship them to you.

TD in DC

What an absolute load of crap! I am very thankful that my service techs are track junkies and honest.

You do NOT want to replace pads and rotors at the same time. If you have your sensors still in your pads, you don't need to replace them until your warning light comes on. I removed my sensors (actually, just zip tied them out of the way), so I inspect mine visually every weekend. You need to replace your pads whenever the pad thickness is equal to or less than the thickness of the backing plate. Easy to check without even removing the wheel. The only thing that should be shaking violently is the tech's neck after he tries to tell you that you must replace your rotors when you replace your pads or vice versa.

As 1999Porsche911 pointed out, the ridge is not a problem per se. The thickness of the narrowest portion of the rotor is what counts. Also, "grooves" on the rotor are not a problem either. Mine are well grooved but my brakes are outstanding.

TD in DC

You can spend $$$$$$$$$ by buying a nice one from snap on tools, or you can do what I did and buy one from Home Depot. Just make sure you get one with a metric measurement scale because the tech specs from Porsche are, of course, in metric. Also, when measuring your rotor thickness, be careful not to bend your dust shield ( or accidentally include it in your measurement). If you do, you might cause it to scrape on the rotor when you are driving. Ask me how I know . . .

TurboMark

Thx TD.

What is the measurement point / metric for when they are too thin?

1999Porsche911

The minimum thickness for the fronts is 1.025 inches and the rears are .875 inches. Use a caliper to measure accurately.

TurboMark

Much appreciated. Also, my caliper is in inches so this REALLY helps! Thx!

jj99c2

TD - why do you say to never replace the rotors and pads at the same time? This is what the dealer normally does for service.

I have a new set of rotors and pads I am getting ready to install and wonder if I should do the rotors first now and then the pads later per your advice?

thx John

TD in DC

No, it should NOT be what the dealer normally does unless they are trying to upsell. If you install rotor and pads at the same time, it becomes harder for BOTH to break-in. Think pad glazing and perhaps smear (ask Jeeva what that is like). It is far better to install new pads, get them broken-in on the old rotors, which should not take very long, and then install your new rotors.

jj99c2

Thanks TD -- so I need to do it the opposite of what I was planning. New pads first and then rotors.

thx John

TD in DC

No problem. Keep in mind that if your old pads still have plenty of life, you can install your rotors first, break them in until your old pads really need to be replaced, and then put in your new pads. I think it probably takes just a little longer to break-in your rotors, so if it were close, I personally would change the pads first, then the rotors.

TD in DC

D'oh! Thanks for pointing out the obvious fact that you can convert. Sadly, I bought a metric caliper without even thinking of converting. Nothing like a brain fart that lingers a little too long