135i rear brake shims

mr.fabulous · 02-10-2015, 03:13 PM

Apologies for the cross-post; I originally put this in the Suspension | Brakes | Chassis section and got no reply.

Daily driver. Replaced my factory brakes (with Posi-Quiet) a few weeks ago. My factory rear brakes included a shim (the fronts did not)... thin and shiny metallic. I wasn't sure whether to install them with the new pads, but I did anyway just to see what would happen (expecting them to squeak, honestly). No issues for the first few hundred miles, but now once warm they squeak like crazy.

Do these shims serve any real purpose? Can I simply take them out, or is it best to leave them and slather the pad side with anti-squeal? Honestly I can't imagine what these things are for.

mr.fabulous · 02-15-2015, 09:38 AM

Well FWIW, I took the rears apart yesterday and slathered some brake squeal stuff between the shims and pads... with zero change in behavior (and I suppose I should take my own advise and bed these brakes in). I still don't know what purpose the shims have.

myBimmerisGray · 09-15-2015, 08:15 PM

Can anybody shed some light on this?

I got a red "brake" light on my way home today, took a look and realized my right/rear shim had popped off somehow. Ride didn't change and I didn't hear any unusual noises.

Is this something I need to hurry up and replace, or can I do without it?

Thanks!

myBimmerisGray · 09-15-2015, 08:19 PM

I'm referring to the clip (#7).

dm874 · 09-17-2015, 11:52 AM

To the OP, yes the shims are important. If you don't put the shims on then whenever you brake for the first time moving forward or in reverse your brakes will slide (very slightly) and lock into place...causing a very loud clunk that anyone near your car will hear (very embarrassing may I say). Ask me how I know. Moral of the story, add that anti-squeal grease and keep the shims in place and hope that the brakes just need some time to brake in.

My BimmerisGray, #7 is not a brake shim but a spring... a shim goes on the back of the brake pad within the caliper. You can only get a red brake light warning from your sensor that tells your car when to change brakes. If you did not reset your on dash monitor for your brake job after you completed the repair then your sensor continued counting down the clock as to when your pads are fully worn (based off of mileage driven). You have to replace your sensor at this point (cheap).

02-10-2015, 03:13 PM	#1
mr.fabulous Captain 209 Rep 893 Posts Drives: Women Crazy Join Date: Dec 2014 Location: Florida Gulf Coast iTrader: (0)	135i rear brake shims Apologies for the cross-post; I originally put this in the Suspension \| Brakes \| Chassis section and got no reply. Daily driver. Replaced my factory brakes (with Posi-Quiet) a few weeks ago. My factory rear brakes included a shim (the fronts did not)... thin and shiny metallic. I wasn't sure whether to install them with the new pads, but I did anyway just to see what would happen (expecting them to squeak, honestly). No issues for the first few hundred miles, but now once warm they squeak like crazy. Do these shims serve any real purpose? Can I simply take them out, or is it best to leave them and slather the pad side with anti-squeal? Honestly I can't imagine what these things are for.
	Appreciate 0 Tweet Quote

02-15-2015, 09:38 AM	#2
mr.fabulous Captain 209 Rep 893 Posts Drives: Women Crazy Join Date: Dec 2014 Location: Florida Gulf Coast iTrader: (0)	Well FWIW, I took the rears apart yesterday and slathered some brake squeal stuff between the shims and pads... with zero change in behavior (and I suppose I should take my own advise and bed these brakes in). I still don't know what purpose the shims have.
	Appreciate 0 Quote

09-15-2015, 08:15 PM	#3
myBimmerisGray Enlisted Member 1 Rep 38 Posts Drives: 2011 128i Join Date: Feb 2014 Location: NJ iTrader: (0)	Can anybody shed some light on this? I got a red "brake" light on my way home today, took a look and realized my right/rear shim had popped off somehow. Ride didn't change and I didn't hear any unusual noises. Is this something I need to hurry up and replace, or can I do without it? Thanks!
	Appreciate 0 Quote

09-15-2015, 08:19 PM	#4
myBimmerisGray Enlisted Member 1 Rep 38 Posts Drives: 2011 128i Join Date: Feb 2014 Location: NJ iTrader: (0)	I'm referring to the clip (#7). Attached Images
	Appreciate 0 Quote

09-17-2015, 11:52 AM	#5
dm874 Lieutenant 84 Rep 501 Posts Drives: 15' M4 Join Date: Jul 2014 Location: Bucks County,PA iTrader: (0)	To the OP, yes the shims are important. If you don't put the shims on then whenever you brake for the first time moving forward or in reverse your brakes will slide (very slightly) and lock into place...causing a very loud clunk that anyone near your car will hear (very embarrassing may I say). Ask me how I know. Moral of the story, add that anti-squeal grease and keep the shims in place and hope that the brakes just need some time to brake in. My BimmerisGray, #7 is not a brake shim but a spring... a shim goes on the back of the brake pad within the caliper. You can only get a red brake light warning from your sensor that tells your car when to change brakes. If you did not reset your on dash monitor for your brake job after you completed the repair then your sensor continued counting down the clock as to when your pads are fully worn (based off of mileage driven). You have to replace your sensor at this point (cheap).
	Appreciate 0 Quote