New front brakes,limitations of rotors?

[moresquirt]

Hi everyone,love this forum even with a 2006 987.1 3.2 S there are many similarities to the older models.I have almost 100000 kilometers (60000 mls) now still with the original rotors (unbelievable) and though they spec out at 26.5 ml (front ) 28 mil new.there are no cracks in the vent holes and no rust anywere,no warpage ect.I did purchase new Porsche rotors and pads ect but decided to just run just another set off pads ,hopefully all will be ok , I do mainly hwy miles and never track the car.I did the pad brake in procedure twice,as i have read that installing new pads on old rotors need extra break-in time so they adjust to the imperfect surface on the older rotors.I will let u know when and what mileage the rotors start to warp or show signs of spider cracks ect.Has anyone here pushed the mileage or limits on older rotors and have some feedback.I figure if porsche states the wear limits are 26 mil there spec on the safe side as some people will be driving thease cars much harder than i with track use ect so taking that into consideration i feel that 25 mil would be an acceptable wear limit.

[LAP1DOUG]

If I wasn't tracking, and had no cracks, I would not worry about it at all. Still, new rotors are awfully cheap insurance, and very easy to change while changing pads.

[woodsman]

Another thing to consider is that as the rotors/pads wear, the pistons are further out of the bore ( their home) and are more likely to get stuck causing all sorts of nastiness such as cooked pads/rotors and scrapped calipers. Ask me how I know. All things in moderation, ya know...

[moresquirt]

I here ya woodsman,good point,i let the pads get down to about 4 mil(part way thru the wear indicator hole in the pad then i herd a squeeking when breaking so decided to pull them,i think the squeek was coming from one pad that was thinner than the rest,maybe 3 mil and the backer plate on the pad starts to rub against the inside slightly raised section on the rotors inside edge next to were the pad rubs on the face off the rotor,i guess thats like a last ditch signal that your getting near metal on metal.
(i have removed the wear indicators as they come on way to soon,can still get another 5000 kilometers before really needing to change them out.I guess i wasent to concerned as i had a new set of rotors standing by just incase,By the way still on my original water pump,and belt also,recently cheaked and all good,no play or strange wear,all bearings still feel smooth and quiet,surprised with everything ive read.

[ekam]

Trouble with wearing the pads all the way down is the brake pistons are extending further to push the pads, which means they're stretching the dust boots. If the dust boots are worn they could crack which then will attract dust/debris into the brake pistons.