K MAN S

Tonight the above warning light appeared. 2020 Macan has 64,000 miles mostly highway.. does anyone have experience how many additional miles can the vehicle be safely driven before changing brake pads? TIA

chassis

Brake light warning comes on with 2.5mm pad life remaining, approx.

MB has a calculation for miles per pad mm but it relates to pad surface area, rotor diameter and force applied, so not directly applicable to Porsche. Having said that, a couple thousand miles should be no problem after the light turns on. I would replace the pads and sensor as soon as practicable.

Rotors are up to you. I replace grooved rotors but plan to re-use front rotors on the Cayenne because they are smooth and the pads are getting down to replacement thickness. Dealers usually recommend or insist on replacing rotors with pads. It is not strictly required.

K MAN S

Thank you for your insight and helpful advice. I welcome any others points of view too.

wingless

Welcome to the forum.

When the indicator lamp illuminates, then the warning contact sender wire must also be replaced. If the pads are replaced w/ greater than 2.5 mm of pad thickness then the undamaged wire may be reused. The pad replacement is required at 2 mm thickness.

WRT to the rotors the Factory Service Manual, FSM, defines many criteria for reuse versus replacement, not just thickness. It also defines limits on cracks, thickness variations and runout. The minimum rotor thickness is typically imprinted w/ cast text on the rotor and also defined in the FSM.

It is also very good maintenance to periodically properly flush the brake fluid w/ fresh. I like to do my vehicles every several years, but certainly at least follow the published service schedule.

My preference is usage of the windshield instead of the brakes, so mine typically last well over 100K miles. My wife's driving style was much more American, gas until stoplight braking and she'd get about 40K miles.

wingless

WRT to the Cayenne, on my Cayenne Turbo I would push it and swap the rotors w/ every other set of pads and be just past the rotor wear limit when replacing the second set of pads.

chassis

Re: the American driving comment, what is your country of origin or reference point?

This week in Germany my taxi driver was late and aggressive on the brakes in city driving. That has been my usual experience in nearly 30 years of traveling to Germany - hard brake application by taxi drivers. A co-worker (German guy) drives his 3er cab 3.0L TDI like he stole it, requiring liberal use of brakes.

wingless

Yes, I'm American w/ about 1M miles behind the wheel.

VERY limited driving experience in Europe, including Germany. REALLY wished I had a larger sedan on the Autobahn as the big MB and BMW vehicles passed my maxed out 3 series like I was standing still...

My experience is bad drivers have ZERO interest to learn / improve / change. It sucks that we have to share the road w/ those brain dead jerks.

jbx2

I replace before the wear sensor trips. Pad and rotor measuring tools are cheap and pay for themselves.

Tim Cooper

Totally agree with this, mine had plenty of meat left when the light came on and they said the sensors were one use only. Discs were about half worn, if in doubt check with a micrometer; there's a little gap in the backing plate just below the caliper.

wingless

The pad sensor is a conductor within an over mold plastic insulator, retained by a metal spring clip.

That low cost part is snapped in-place during brake service and is easy enough to transfer between pads, assuming the plastic hasn't been worn away by the rotor.

Denny Swift

New pads are about 9mm. 64,000/ (9-2.5) is about 10,000 miles per mm. That's as good an estimate as any.

wbferran

I can’t quite follow the math here. Where is the 64,000 coming from? Thx

Denny Swift

You said you have 64000 miles on the original pads

wbferran

thx. I see that now from the OP K Man.

Has anyone else experienced anything close to this? 64,000 on one set of pads? Maybe it was a typo?

wingless

This 100% depends on driving style and conditions.

My usage of the windshield gets me well over 100K miles on a set of pads.

My family members who are on the gas until braking at the red light get under 40K miles on the pads.

Also, high throttle in snowy conditions will cause the vehicle's stability control to wear the rear pads.