Brake issues - 986 Forum - The Community for Porsche Boxster & Cayman Owners

I'm having trouble with the brakes on my 97 boxster. It needed new brake pads. No problem, or so I thought. Replaced the pads on all for corners. Took the car it for a test drive. Everything seemed ok until I noticed it was slowly decreasing speed. Noticed that the brake pedal was getting hard to push down. The end result was stranded a couple miles from home with smoke coming from the brakes. They were heating up slowly and then pretty much locked up the front completely and the back brakes were very hot as well just not smoking like the front. After the car sat for several hours and the brakes cooled off I was able to get it home. Took it to a mechanic and after a new master cylinder and brake booster I am still having the same issue. Mechanic says he doesn't think it's the calipers. I disagree with him. I'm guessing that when pressing in the pistons to get the old pads off something went wrong with the calipers. I checked the brake lines and I dont see any damage to them. Anyone agree to go with the calipers or am I missing something else? Thanks in advance.

Quotes source post: 597563

Did you at any time during the brake change leave the calipers hanging from the brake hose? I've heard it's possible to damage the inside of the brake hose. While it's not noticeable from the outside, it can act like a check valve. The overwhelming force from the master cylinder can push the fluid through in one direction, but the restriction holds the pressure on the piston side, so it doesn't retract. I'm talking about the rubber hoses, not the metal lines.

No, I never had the calipers off while doing the pads. I just did an easy brake pad replacement. Someone did ask if I crushed a line or damaged one. I looked but didn't see anything.

first, is it all four wheels or a couple of wheels or one? It seems from the symptoms that the brakes are getting hot, swelling a little and forcing the car to stop. I have had this happen on motorcycles before after brake pad changes and it was stuck calipers. Basically, the piston was used to being fully extended because of worn pads, then when I replaced the pads, hitting the brakes extends the piston and it doesn't want to return all the way. Everything is fine until the brakes heat up and seize. I had to rebuild the caliper. I doubt all four wheels seize, but one or a pair is conceivable.

also, i will add: I'm concerned that your "mechanic" didn't look straight away at the calipers. We could all be wrong, but that is the most likely point of failure, 99 out of 100. Tell us what you find out, Huh?

This mechanic was referred by a friend. I will not go back. The front brakes are locking up after about 6 miles of driving. The back ones are getting hot but not nearly as bad as the front. This mechanic said that they had the calipers off and the pistons were going in and out like they were supposed to. I've talked to another guy who had the same problem. Looked at the calipers and were working. They ended up putting new calipers on and low and behold that fixed the problem. I have found some reman calipers. Think that's the next step. Will definitely let 8know the outcome.

Quotes source post: 597573

so this brings up a question I have...I have the Boxster S and should I want to rebuild the calipers, the kits are unreasonably expensive. Aren't these 4 piston Brembo? 36mm/40mm Front Pistons 28mm/30mm Rear Pistons? why cant I just get a brembo rebuild kit in the proper caliper sizes? Is there an alternative to the kits anyone can turn us onto?

Would these work? 28mm/30mm, 36mm/40mm Stoptech/Brembo Brake Caliper Rebuild Kits (Qty 2) | eBay https://ebay.us/kQCIvZ Sent from my iPhone using Tapatalk

Boxster S calipers are Brembos

Quotes source post: 597665

understood, so would Ohio performance (oddly out of Missouri) rebuild kits for brembo in the proper diameters work? what else would I need to replace to refresh 20 year old calipers?

Giro disc has everything you need, just give them a call they’re great to deal with. Don’t make the same mistake I did and go with other companies to save a few dollars. The tolerances on the piston seals are so tight that you won’t be able to get your piston back in if tolerances aren’t strictly adhered to during production. Good luck Shawn Edit: girodisc on their website doesn’t seem to support the 986, but I’d still call them.

996 should work for Boxster S Sent from my iPhone using Tapatalk

986 S has the same brakes as a 996 non S. Not sure about a 996 S

Quotes source post: 597725

Fair enough, add that giro brake is pretty pricey, considering what is out there. I think I am pretty safe going with the ohio performance seals and boots, but will email off for application in advance. The seals look VERY nice, claim high temp siliconized etc and giros look kinda gummy. anybody use the ohio performance stuff before?

FYI, First gen cars are prone to waterlogged brake boosters. I had similar problem with my 99. I have a Tip and noticed there was no "creep" at stoplights. Prior to 2000 the cars had a 2 piece bellows that connected the brake rod from pedal to booster. The part that the rod goes through allows water to get in and corrodes the inner part of the booster rendering it useless. I was lucky I have heard some people have the opposite problem, No stopping and back up into things. Easiest way to check is to pop off the vacuum line to the brake booster in the frunk and stick your finger in try to find the water level or something that will absorb water to see if that is the problem.

have 2000 boxster S and will be looking closely at the booster and Master cylinder. they are 20 yrs old so possible it's time to replace.. watched a number of videos and can't believe the design allows water to seep in... planning to pull the mc and booster and replace with new, bleed and hope that solve my issue.. that issue being, i was driving about 55 mph and the rear brakes starting clamping without me even on the brakes... pulled of the highway and lucky was able to get close to plaza though stuck in middle of road... cooled down about 20 mins and drove home... no issues drove again after a week and same problem and brakes no letting go.. only weird thing i did was pull the car out of winter storage after about eight weeks no driving... previous last drive was through a snow storm so may took in some moisture or salt... the boxster performed well with snow tires and about 4-6 inches of accumulation in about 3hrs... then got to rainy wet area so had some water or road salt mixed in, parked it eight weeks, pull it out of storage this problems shows up