Uneven brake pad wear

mclemens · 08-01-2012, 11:38 AM

I changed the rear pads on my 1M today and found that the pads on the drivers side had really uneven wear. The front edge of one pad was wore much more that the front edge of the other pad. This condition was reversed on the back edge of the pads. Take a look at the photo to see the angled wear.

On the passenger side the pad wear was the same (nice and even) on both pads.

Any idea on what would cause the uneven wear?

MDORPHN · 08-01-2012, 12:21 PM

Sticking piston, possibly caused by damaged dust boot??

Neil

TXmtrhed · 08-01-2012, 03:54 PM

Quote:

Originally Posted by MDORPHN

Sticking piston, possibly caused by damaged dust boot??

Neil

I don't see how that could be the case; the outboard pad wear should not be affected by the piston - it's alignment is determined by the caliper. This kind of wear is extremely odd. Looks like the whole caliper has been cocked at an angle. Are the guides and guide bolts in good shape?

Wolfpack · 08-01-2012, 08:29 PM

Really strange for a rear pad to do this. I used to have this on the fronts of my 330 before I changed to brass guide pins and got rid of the rubber. Really seems like there is way too much pressure applied and the calipers are deflecting. Just never seen it on a rear before.

HP Autosport · 08-10-2012, 12:21 AM

The guide sleeves are rubber so under load the caliper will try to twist on you. To minimize this issue you can install caliper bushings as the cheaper route or BBK.

08-01-2012, 11:38 AM	#1
mclemens Enlisted Member 10 Rep 43 Posts Drives: 2011 BMW 1M Join Date: Jan 2012 Location: USA iTrader: (0)	Uneven brake pad wear I changed the rear pads on my 1M today and found that the pads on the drivers side had really uneven wear. The front edge of one pad was wore much more that the front edge of the other pad. This condition was reversed on the back edge of the pads. Take a look at the photo to see the angled wear. On the passenger side the pad wear was the same (nice and even) on both pads. Any idea on what would cause the uneven wear? __________________ 2011 1M AW, 2011 A3 TDI, 2013 Mini JCW, 2014 F150, 2016 Focus RS on order
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08-01-2012, 12:21 PM	#2
MDORPHN Colonel 291 Rep 2,898 Posts Drives: AW 1M Join Date: Oct 2010 Location: Wash, DC iTrader: (0)	Sticking piston, possibly caused by damaged dust boot?? Neil
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08-01-2012, 08:29 PM	#4
Wolfpack Private First Class 1 Rep 199 Posts Drives: Everything in my garage Join Date: Aug 2007 Location: Iowa iTrader: (0) Garage List 1999 Mercedes ML320 [0.00] 2006 MINI Cooper S [0.00] 1997 Mazda Miata [0.00] 2011 BMW 1M [0.00] 2002 BMW 330 Ci [0.00]	Really strange for a rear pad to do this. I used to have this on the fronts of my 330 before I changed to brass guide pins and got rid of the rubber. Really seems like there is way too much pressure applied and the calipers are deflecting. Just never seen it on a rear before. __________________ Wherever you go...there you are.
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08-10-2012, 12:21 AM	#5
HP Autosport Supreme Allied Commander 3816 Rep 54,319 Posts Drives: F80 M3 Join Date: Mar 2007 Location: Santa Barbara, AP, Brembo, GIAC, Koni, Ohlins, Performance Friction, www.hpautosport.com iTrader: (36)	The guide sleeves are rubber so under load the caliper will try to twist on you. To minimize this issue you can install caliper bushings as the cheaper route or BBK.
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