Bob Schoenherr  Tech Tips: Maintaining Your Porsche's Brakes
  by Bob Schoenherr, Redwood Region Membership Director

This month, Chris has asked me to provide info on doing a brake job on your Porsche. First and foremost, it is highly important that you do NOT attempt this yourself unless you feel confident that you have the correct directions and mechanical ability to:

  •    take apart your brakes
  •    measure the wear of the brake parts
  •    reassemble your brakes
  •    test the brakes properly

Remember: SAFETY FIRST. As soon as any brake problem is noticed, get it repaired immediately. Delaying brake repairs is extremely dangerous. The longer you delay fixing brake problems, the more you increase the cost of doing so and, more importantly, you are putting yourself at risk. If at any time you feel a "spongy" brake pedal or one that gets lower underfoot you need to look into finding the problem immediately.

There are so many models of Porsches today, from 356 to 991, that it is best to check forums and repair manuals for a list of tools, part specifications, and step-by-step directions. At the end of this article are some DIY (do it yourself) links for your viewing pleasure. 

  • Brake rotors (discs): Inspect all the way around the surface and on both sides for any concentric scoring (grooves) or obvious defects. If defects are found, replace your rotors immediately. Any rotor discoloration may be a sign of overheating and more damage than you want to deal with. Take your car to Hi Tec or one of our other sponsors for professional assistance.
  • Brake pads: Generally, rotor scoring matches on the pad. Inspect for uneven wear, breakage, or cracking on the friction surface. If defects are found, replace the pads immediately. 
  • Newer cars have brake pad sensors to warn of pad wear. If you are replacing your pads, it is a good bet that the sensors should be replaced too.
  • Brake drums on older Porsches should also be inspected on a regular basis. You need to remove the drum to do so. The drums should not have excessive grooves or have a deep "trough" dug into them where the shoes ride.
  • Brake shoes on older Porsches should be worn evenly and have no rivets protruding to the friction surface.
  • Check calipers, wheel cylinders, hoses, and fittings for any hydraulic fluid leakage. Inspect the master cylinder, reservoir, and proportioning valve assemblies as well.

Use your ears every day to listen for the following:

  • Know how your brakes should sound and listen for abnormal noises when driving the car. Find a high wall or drive between buildings with your windows down. This makes picking up the sounds easier.
  • Beware of squeaking, which may be caused by dust or dirt on the brakes, loose pads vibrating when applied, or worn pads.
  • A rhythmic noise or pulsating noise might mean you have a warped rotor.  In extreme cases, warped rotors cause the brake pedal also to pulsate underfoot. Don't confuse this with ABS feel.
  • Any constant brake noise means stop the car and start looking for the problem.

Once a year you should check:

  • "Run-out" - this is measured by placing a gauge on the part, and rotating the part 360 degrees. The total variation is recorded as the runout.
  • Warping
  • Wheel bearing play

Recommendations to follow:

  • Keep the hydraulic reservoir at the proper level with the fluid type recommended by Porsche. Never substitute or mix types of fluid. Never use old hydraulic fluid. Always use a fresh container.
  • Keep brakes clean by washing them off at the same time as your car. This keeps squeaky dust and dirt off the pads and makes brakes easier to inspect and work on.
  • Never spray, touch or drip any oil or lubricants on the brake friction surfaces. If this occurs, clean it off IMMEDIATELY.
  • Know your brake system - how it should work, feel and sound - before it acts up, so you'll know when something's wrong.
  • Check rotors for correct thickness. Replace the rotor at the same time as the pads if it is out of spec.
  • Keep a repair log with receipts when any service is performed on your Porsche.  Too many benefits of this to list!!!!
  • After installing new pads, remember to "set" them properly. This conditions them for maximum performance and prevents premature failure. Instructions for setting pads is usually provided in the package with your new pads.

If shopping for Porsche brake parts, remember two important things:

  1. OEM/OES (original equipment manufactured/supplied) or equivalent pads and rotors are not always cheap. You do, however, get what you pay for. OE parts will give you the most trouble-free driving and peace of mind. And...isn't that what's most important?
  2. Before requesting any brake parts for your Porsche, make sure you have the year, exact model designation, engine size and type, brake configuration, type of rotors (solid or vented), vehicle ID number (VIN) and production date.

As for replacing your brakes, most cars today use disc brakes, so lets give you the basic steps assuming all braking components are in good condition:

  1. Jack up your car and place the car on jack stands, then remove the tire.
  2. If you are going to replace the rotor, loosen the rotor holding screws Some cars have them and others do not.
  3. Remove the brake pad pin or pins.
  4. Remove the brake pads.
  5. Compress the caliper pistons.
  6. Insert new pads.
  7. Reinstall pad pins.
  8. Before driving the car, PUMP UP YOUR BRAKES. The pedal will feel spongy because you depressed the caliper pistons.
  9. Now break in the brake pads by driving about ten miles or so. Do easy stops at first, and then some stronger stops.  Check the recommendations of the brake pad manufacturer for correct break-in.

Bob




Helpful links:

Brake Job on Boxster S (skip the rear axle removal at the end): 
http://markitude.wordpress.com/2012/01/04/brake-job-on-porsche-boxster-s/

Great Cayenne DIY
http://forums.rennlist.com/rennforums/porsche-cayenne-forum/451429-diy-front-rotors-and-pads-for-the-cayenne.html

6speedonline Forum DIY
http://www.6speedonline.com/forums/996-turbo-gt2/178732-diy-brake-job-mintex-pads-review.html


Video - How to replace front Brake Pads on a Boxster
http://youtu.be/V-SotOWfsOI

Front Brake 996, Part 1
http://youtu.be/CC16WXBcE7Q

Front Brake 996, Part 2
http://youtu.be/--6HLa3Vays

Rear Brakes with Parking Brake adjust on 996
http://youtu.be/9DpC0lXHP5o