NOTE on checking brake wear: be sure to check the outer AND INNER pad thickness

rumatt · 04-11-2007, 06:37 PM

My front sensor had fallen out and I lost the little metal clip. I was meaning to buy one but I figured it didn't matter because the fronts had a lot more life than the rears.

Well, the rears finally tripped. I checked the fronts and the outer front pad still has about 3-4 mm left, but the inner pad is completely gone. Metal on metal.

About one month ago the inner and outer pads were about equal, so the uneven wear must have come right at the end. I guess this may make sense because the pressure on the pads might change as it gets near the end (and the thing is fully extended or whatever) but I sure wasn't expecting it.

FC · 04-11-2007, 06:51 PM

Thanks for the heads up.

bren · 04-11-2007, 09:24 PM

It's also wise to remove the pad to be certain the wear is even across the entire pad surface.

rumatt · 04-12-2007, 10:37 AM

Quote:

Originally Posted by FC

Thanks for the heads up.

Well, the sensors are on the inside pad, so as long as they're in you should be fine.

Pinecone · 04-12-2007, 10:37 AM

Although the tendency for single piston setups to wear the outer pads faster.

I would check the piston seal carefully when I had it apart.

rumatt · 04-12-2007, 10:40 AM

Quote:

Originally Posted by Pinecone

Although the tendency for single piston setups to wear the outer pads faster.

I would check the piston seal carefully when I had it apart.

Well, the dealer has it now. Maybe they'll do the right thing and inspect it all under warranty.

Nick M3 · 04-12-2007, 10:42 AM

Quote:

Originally Posted by Pinecone

Although the tendency for single piston setups to wear the outer pads faster.

I would check the piston seal carefully when I had it apart.

I have never once seen a pad out of a BMW with greater wear on the outside.

John V · 04-12-2007, 10:57 AM

Quote:

Originally Posted by Nick M3

I have never once seen a pad out of a BMW with greater wear on the outside.

I've never seen a sliding caliper with more wear on the outside. My M3, Clyde's car, my SHO, all of 'em wore the piston side first.

Rob · 04-12-2007, 11:52 AM

There was an M Coupe that went into the trees off of some track with two instructors from the Windy City chapter in it (the safest and most careful BMW schools that I am aware of). The instructors had checked the brakes, but failed to check the inside pads. That is a practice the chapter now harps on, but the car gave it's life so the instructors could teach another day.

kognito · 04-12-2007, 12:58 PM

Quote:

Originally Posted by bren

It's also wise to remove the pad to be certain the wear is even across the entire pad surface.

04-11-2007, 06:37 PM	#1
rumatt Mugwump Join Date: Oct 2003 Carmudgeonly Ride: E46 330i, Chevy Colorado, Tesla Model 3 Location: NY Posts: 17,475	NOTE on checking brake wear: be sure to check the outer AND INNER pad thickness My front sensor had fallen out and I lost the little metal clip. I was meaning to buy one but I figured it didn't matter because the fronts had a lot more life than the rears. Well, the rears finally tripped. I checked the fronts and the outer front pad still has about 3-4 mm left, but the inner pad is completely gone. Metal on metal. About one month ago the inner and outer pads were about equal, so the uneven wear must have come right at the end. I guess this may make sense because the pressure on the pads might change as it gets near the end (and the thing is fully extended or whatever) but I sure wasn't expecting it.

04-12-2007, 10:37 AM	#5
Pinecone Carmudgeon Join Date: Dec 2004 Location: Maryland Posts: 2,717	Although the tendency for single piston setups to wear the outer pads faster. I would check the piston seal carefully when I had it apart. __________________ Terry Carraway 2002 Topaz E46 M3 2000 Dakar M Roadster 1995 Alpine E36 M3 LTW 1990 Red/White Spec Racer

04-11-2007, 06:51 PM	#2
FC Solving problems Join Date: Oct 2003 Carmudgeonly Ride: M5 / 718 GTS / Cooper S / GTI / LR4 Location: Metro Boston Posts: 25,264	Thanks for the heads up.

04-11-2007, 09:24 PM	#3
bren lawn boy Join Date: Oct 2003 Carmudgeonly Ride: e46m3, f25x3,C5 Z06, C4 Vette, 06 CTD Ram, and a trailer Location: Maryland Posts: 14,029	It's also wise to remove the pad to be certain the wear is even across the entire pad surface.

04-12-2007, 11:52 AM	#9
Rob The user formerly known as rwg Join Date: Oct 2003 Carmudgeonly Ride: Z4 Location: Vegas baby! Posts: 8,261	There was an M Coupe that went into the trees off of some track with two instructors from the Windy City chapter in it (the safest and most careful BMW schools that I am aware of). The instructors had checked the brakes, but failed to check the inside pads. That is a practice the chapter now harps on, but the car gave it's life so the instructors could teach another day.