Worn Brake Pad sensors

I just got the message on the dash. Is there a way to tell which wheel or at least which axle tripped it? Anyone have a good guess how much pad is left? 1000, 5000, 10,000 miles?

I think a scan tool with Porsche -specific software might tell you the location, but at this point it shouldn't matter. If I do pads ALL the sensors get replaced. They get very brittle from the pads' heat; getting them out intact is about 50/50 success. Usually, you're safe for around 500 miles when the light goes on, but that also depends on how heavily and how much you brake. Some people are very easy on brakes, some people use the accelerator and brake hard, other people use engine braking. There is no hard and fast rule. BTW - I'm fixing the thread title - its BRAKES now "breaks" - that's like squealing chalk on a blackboard for me..

Knowing the sensors will be brittle from heat is most of the battle in preservation during removal. However, Don is right when doing all the brakes it's best to have new replacements. The last thing anyone needs is to be on the job, lose some sensors and not have new ones within arm's reach. Don's "breaks" tips are solid. PS downshifting to slow the vehicle sounds cool, works like a charm and is certainly a choice but my personal advice? Brakes are cheaper to replace than any other component being used to slow the vehicle.

I don't know what wheel/tire package you have but on my 07 Cayman S , I can easily look through the open space of the wheels and see the leading edge of the brake caliper. Generally speaking, think of a new pad as being 1/2" thick and see what you actually have. This is just a quick check, but if one or more are clearly worn down to a thin strip on brake material on the metal backing plate (Thin would be 1/16"), then there you go, schedule a service soon. Everybodies access to work on their car varies but if you pull each wheel so that you can get a good look at your calipers, allowing you to see the inner pads. There is a small chance that one pad is dramatically thinner than the rest, which would point to a sticky caliper. This would be good to know going in, as it ups the cost, time, and complexity quite a bit over a straight pad change. Also run your finger over the outer diameter of your brake discs (can also be done with the wheels on the car). As they wear, they leave a ridge around the outside edge. Subjective, but if it feels like it is worn more than 1/16", you probably need to replace the discs. There is a hard wear limit in mm's in the Porsche specs but 1/16" will get you in the ballpark. I replaced all the wear sensors on my 07 Cayman S . I had several go arounds with the parts vendor getting the right ones. There were subtle differences. If you hear a new sound of metal on metal grinding when you apply the brakes, your remaining mileage is zero!

My personal experience (I learned to drive in an era when brakes were somewhat marginal, and everyone used engine braking - and almost everyone drove stick-shift).. I have owned numerous cars that were well past 100k miles on the original clutch and driven with some use of engine braking. Not severe engine braking, but enough to be of assistance. It also is a good driving technique since just like a PDK - you've preselected the gear you'll want to be in if you can stop braking (like traffic clears up or a light changes ahead..). The most miles I've seen from an original clutch was 275,000 miles on a '69 Volvo 1800S. I owned it to 175,000 miles - original clutch, complete with engine braking. I then sold it to a neighbor who took it to 275,000 miles - same clutch. He sold it to another guy who tracked me down as a former owner and contacted me. He was trying to find out if the clutch had ever been done. It hadn't been. He seemed to feel it was getting near needing a new disk. I think dual-mass flywheels may change this somewhat, but done in a sane manner, I have no issue with engine braking - my PDK does it all the time.

I was not planning on reusing sensors. The car is my daily driver (About 1 K a month) MBs give me an easy 5K mile or more after the sensor lights. It would be great to make spring just for a more comfortable job. Also some cars wear one axle much faster than the other, so figured, if I was in a pinch I would do one end. Most MB and Audi do one wheel on each axle, but some higher end models do all four wheels. Just wondering what a 987.2 base has.