Sprayy

Hey guys,

Put on brand new rotors/HP+ pads, bed them and went to the track yesterday.

On the way back home and today the brakes squeal under 10-40% pressure on the brakes. They're fine if you go hard on them. I tried rebedding but no luck.

The car is undrivable like this, I'm used to brakes squealing but it literally sounds like a train derailing everytime I slow down. Pedestrians and drivers are whipping their heads around in a panic lol.

dcamick

Have you checked for a broken/damaged pad? Front or Rear? Year?

Mordeth

The first thing you need to do is dump the junk HP+ pads. No good on the street, no good on the track. No good anywhere, and don't let anyone tell you otherwise. They squeal like stuck pigs on the street, emit horrible corrosive dust, ruin perfectly good rotors and fade like hell on the track. Biggest piles of **** ever made. They do nothing well and everything bad. Jack of no trades, master of no trades.

If you are driving on a race track, get some real, dedicated track pads. Carbotech XP12/10. DTC70/60 etc etc. They will squeal on the street, which is why you swap them for street pads like the Carbotech 1521 or Powerstop Z26 when you go back to street driving.

So to summarize:

1) Dump those POS pads immediately
2) There is no such thing as a good "dual purpose pad". If you want a track pad, they will squeal on the street as they don't reach proper operating temperature. If you want a street pad they will fade rapidly on the track and stop working. The safe thing on the track is a track pad. The quiet thing on the street is a street pad. They are designed to operate in different conditions and different temperatures. This is how it goes.

So get both, and take 20 minutes to change them if the car is used for both track and street. My wife changes my brake pads when I'm busy, so don't be afraid of this simple task.

Sprayy

Thanks for the write up. I need to find a good brake pad swap tutorial!

Mordeth

I will write one now. Mine are changed every two weeks.

Tools needed: 19mm socket, 21 mm socket, socket wrench, 18-24" breaker bar wrench, tube of brake lube, flat head screw driver for prying purposes, C clamp, jack, jacking pucks, jack stands (if you want to be safe), PB Blaster/WD40, Torque wrench capable of at least 130 ft-lb, gloves, rags, box, emery paper (optional).

1) Break lug nuts using 19mm socket and place jacking pucks.
2) Jack car up from jacking pucks.
3) Place jackstands appropriately and a place a random box you have laying around under caliper (will be used later)
4) Finish removing lug nuts and then remove wheel
5) Use a wrench with a 21 mm socket on the two large bolts located at the BACK of the caliper. You can't miss them. One on top and one on the bottom going through the back of the caliper. Unbolt from BEHIND the caliper (under the car). May have to lay on your back if you can't reach. Also may need a breaker bar or long, sturdy wrench for leverage at first to get the bolts loose, as they are on very, very tight. If stuck on, use PB Blaster or WD40, put your purse down, use breaker, make sure you are turning bolt the correct way and try again. Once bolt is broke loose, just wrench it fully loose of the threads then pull it out.
6) Once bolts are removed, pry caliper off rotor. May require persuasion
7) Place caliper carefully on your box from instruction 3 to support it so that brake lines don't pull off
8) Compress all pistons on each side of caliper with old pads still in. A simple $3 C clamp will suffice. Just put clamp on, tighten then loosen. Pistons will compress. This makes it easier when new pads go on as they will be thicker and may not clear the rotor due to pistons being out. You can open the brake reservoir inside the engine in case fluid is pushed back through. Place a rag around the area in case it splashes. Remove clamp.
9) Pry out/remove old pads. May need a little persuasion with a screw driver or fingers, may just fall out if caliper is turned over. Anti-rattle clips can stay in if you are careful
9a) Clean caliper thoroughly (good time to do it). Nothing fancy, just clean it up.
9b) Inspect rotors. You can do a light sand using 80-100 grit emery paper if you are feeling fancy
10) Lube up new pads with brake lube on the non-friction surfaces (sides and back). The **** gets everywhere so keep a rag handy. If you don't know how to apply the lube, don't use it. You basically just smear some of it on the backing plate and sides. DO NOT LUBE THE FRICTION SURFACE (PAD).
11) Place new pads in caliper with pad/friction side facing the correct way. If you don't know the right way, think in your brain about what is going on, then place on them the way that would make sense for the friction part of the pad to compress onto the rotor, ie., common sense. Align old anti-rattle clips as you are placing pad in caliper. It is a little tricky. The clips need to kind of be half installed as you insert the pad. Use the end of a screwdriver to "push" the clips in, being careful not to bend the clip. They will snap in snugly once done right with the pad installed. May take a few tries. You are smart and will figure out this tricky but simple task.
12) Replace caliper on rotor. It may take a little jiggling and encouragement to get it back on with the new pads in the caliper. Caliper will slide/clamp on rotor in a satisfying way once aligned and pushed back on properly.
13) Re-install both rear caliper bolts. Use some blue loctite if you feel like it. Get them started with your fingers. May have to adjust caliper slightly to get bolt holes aligned. Then crank them down and tighten to 129lb/ft using torque wrench. It will take a bit of muscle as the angle isn't that great to get the torque wrench to click to that. Put purse down and use a sturdy torque wrench and make sure you have leverage.
14) Inspect your work.
15) Place wheel back on car and tighten lugs snug.
16) Rinse/repeat for each corner
17) Lower car and torque lugs on wheels to 100lb/ft.
18) Before moving car, pump brakes until they regain pressure and feel firm. For the first "move" of the car, be very careful and slow until you are certain your brakes are working and pedal has pressure. Then take a nice slow drive to ensure all is functional.
19) Drink a beer

There is always the chance of additional steps if you encounter any issues, but the above are the basics. I can do a wheel in 5-7 minutes. 10 minutes if something decides to make life difficult. You should be able to do a wheel in under 20 minutes. Good luck.

Sprayy

Hawk is telling me this is completely normal. It's literally heard for blocks away and constant. Is it normal for it to be THIS earsplitting loud?

philadd

For HP+, yes.

harrydirty

Excellent tutorial on replacing brake pads.

One suggestion to make things easier is to turn the steering wheel all the way over after wheels/tires are removed so the caliper is exposed and easier to access. For the right/passenger side, crank the steering wheel all the way left, opposite for the left/driver side.

Bill Dearborn

Jeesh,

You might think he doesn't like the pads after reading this. He even followed it up with a stronger message.

Bill

blkbrd69

"Real" track pads squeal like a school buss towing a dump truck on the street. Nature of the beasts when cold.

I don't consider HP+ track pads. I have never found a true track pad that does not squeal like a stuck pig on the street after the bedding is worn down due to cold track pad abrasiveness. I never had any luck with Carbotechs lasting worth a darn. Had good luck with ST-47 & 43, Cobalt XR 1 & 2, Hawk DTC 70 & 60.

Many of us consider pad squeal to be a badge of honor, the sound of track credentials.

Get good at changing pads. A Milwaukee impact with a swivel socket is worth its weight in gold.

anth115

Just want to chime in with my $0.02:

- Yes, undoubtedly a dual purpose pad will always be a compromise, be it in terms of noise, dust, or function when cold or hot. But depending on how often you track your car and how handy you are, this may make the most sense. Just think it through with your particular situation in mind.

-Here's something that wasn't brought up yet: How new are you to tracking (this car/this track)? When I was new in my M3 I was inadvertently dragging the brake a good bit, which glazed the rotors (doing this at such high speeds produces tons of heat). This led to squealing on the street, even though no visible deposits were on the rotors. I tried rebedding too on the street (10x stops @60mph or whatever the spec is), but that wasn't enough. I did another HPDE weekend, didn't drag the brakes, and now all is well on or off the track. No new pads needed. So maybe give that a try.

Dan_the_C5_Man

Agree with Mordeth about the Hawks (EBC is the same deal), and also about the Carbotechs (good stuff).

There IS one setup that excels in both street and track day use, and that is the Z07 / ZR1 CCB configuration.

It's what I run, and they are excellent. Yes, big $$ to convert. :

986_C6

My list from best to ok DTC70, ST47, XR1/2. You can hear them a mile away!

09C6zo6

Mordeth

I really need to put on the AP Racing CP9668 big brake kit with 1 inch thick pads. Starting to get sick of changing my racing pads every 2 weeks. Just had to do it at the track last week during lunch on a borrowed jack and a flimsy wrench that was laying around....in the rain on my back. Starting to get old.

STANG KILLA SS

high performance track pads squeel like a mother. especially with low pedal inputs.

my HP+ pads squeeled on the street too. no noise on track though.
real race pads squeel all the time and dust like a mother.

this is all normal.

63Corvette

I recommend Stoptech "Street Performance" pads, which are now renamed "Sport". They are good for 1300 degrees F, and are also cheap