Thanks Marc! (more)

Hi all. Patient: 2004 986 non-S 2.7 MT

I've changed my brake pads ( 3x) and rotors (1x) without issues. No noise, normal wear, etc.
Use is daily plus autoX (8 days/yr) and track use (about 6-8 days/yr).

Parts have always been "OEM replacement" ; various brands.

Last fall i did both pads and rotors (3rd job). This was different. Ever since they have squealed badly. Also , they have worn with a huge taper from the leading edge (which is now GONE) to the trialing edge which is 6-8mm, or about 50%. All 4 wore identically. Pretty odd eh? Killed them at Lime Rock this week and an AutoX today.

Now i'll say what was different, although none really explain much:

1. pads were Pagid OEM - previous were Brembo (factory), Jurid, Textar
2. Pad backing plates were loose and never seemed to adhere correctly.
3. Pads were installed with only 1 normal day use before trip to VIR. So much break-in/bedding was done en route to VIR, in the rain, and then at the track. But so what, many put pads in AT the track.....

Any idea what might have cause these issues? Any idea how/if they might be related?

Grant

which tends to interfere with the natural retraction the pistons have which pulls the pads away slightly from the rotors. Because of this drag this pulls the leading edge of the brake pads into the rotors and results in accelerated wear.

Last brake job I found 1 pad worn this way and the others ok.

Sincerely,

MarcW.

Push the pistons in and out to clean the lip? Maybe even lubricate them with some clean brake fluid?

Grant

Brakes appear to be holding up quite well though I haven't bothered to check the pads for wear yet. I'm just going to let the warning light let me know and then I'll look at the pads and see what the wear pattern is like.

Ideally my belief is the cleaning should take place just bofore one digs into the brakes. This catches the pistons out about as far as they'll ever be which means the covers are as exposed to cleaning as they'll ever be. Pre-cleaning also makes the brake job a bit less messy since one is working with less dirty/brake dusty hardware.

In between brake jobs, as I have mentioned before, I try to treat the wheels/brake hardware to an occasional washing which sees the water run almost black for a moment as the dirt gets flushed off the brake hardware, and this includes of course the piston covers.

You do not want to push the pistons out too far for fear one or more will come out of its cylinder. Also, you could push the piston into an area of the cylinder where it hasn't been before and if there is any corrosion or abrasives that have collected there this can damage the piston seal.

Sincerely,

MarcW.

I dug in. While the pistons were not "seized", they were also not moving smoothly. So i followed your advice. I guess i never appreciated that brake cleaner is so much more than cosmetic. It clears grit out. I put some old pads in (uniform, 1.5mm pad left, brembo) so they pistons would come all the way out - and after cleaning and basting with brake fluid ( i got a little squeeze bottle and filled it wih clean, but aged stuff) i can now take my handy-dandy channel locks and squeeze one side and watch the other set move in perfect unison. Whoopee - new track-ish pads here i come!

FYI i am putting in Stoptech 309s next. I'll report back after road use and then after track use (not sure when my next track excursion will be).

Grant