I just installed new brakes and rotors all around on my 2006 MCS this past weekend. I noticed that the rear brakes rub slightly – enough that they are hot to the touch (but not scorching). The fronts do not do this. When I was reinstalling the rear wheels I could feel the rub but could still turn the wheel by hand against the resistance. Also I could smell the rear brakes slightly after parking in the garage.

Is this normal or anything to worry about? I had no problems reinstalling the calipers, so I know that I was able to retract the pistons all the way. Will the brakes eventually wear enough that they won’t rub anymore (without causing any significant damage due to hot rotors)? Or should I take them apart and re-retract the pistons?

 

If it were me, I'd take them apart again, re-retract the pistons, and re-assemble, making sure everything was clean, pads were in the right way, seated fully, etc.
just for the peace of mind.

 

remove the wheels and make sure the rear inside pad is still clipped to the piston.

 

No, that's not normal. Find a how-to and look at the backside of the inboard brake pad. There is a retainer clip on it that attaches to the piston in the caliper. If this is not attached, it will rub and make noise. This will only be on the rear calipers. Good luck----

 

AHA -- I think this might be my problem. Here's the backside of the inboard pad. How does this retaining clip attach to the piston? Do I have to somehow bend it into place? First time I just put the pad in the carrier and reinstalled the caliper.

 

there is a grove around the top edge of the piston, those clips fit on 3 "sides" of the piston. I'll look for a pic I have and post it ASAP.

 

This pic is with the clip installed right


This is with it wrong

Hope that helps.

 

Thanks! That was exactly my problem. Got it put back together right, and all is better -- no more dragging brakes.

It was a bit of a PITA to get all three of those springs inside the piston groove. Interestingly, the Bentley manual makes only one small mention of this ("Rear brake pads: Make sure inner pad is correctly seated in caliper piston groove") and OctaneGuy's lengthy write-up on changing rear brake pads makes NO mention of it...? I wonder if he didn't even know? He just writes "There wasn't anything particularly difficult about putting everything back together again. Just slide the caliper assembly on, and tighten the 2 Allen head bolts. "

Nonetheless, thanks again to you and DAVESTER. These forums are a lifesaver. I would have never figured this out otherwise.

 

Glad it went well for you and your welcome--

 

Well, sit me down and call me Susan! My rear brakes are also rubbing slightly after I installed all OEM pads and I will have a look at them ASAP!

 

sh-t on toast! Better go home and check mine also!

 

sure enough, I'd done it wrong. Learn something everyday I guess.

 

LOL. I had the same thing happen to me. Couldn't figure it out. Somebody on NAM helped point the clip thing out to me, and sure enough, that was the exact problem!

I feel better now, knowing that I wasn't the only dummy...

 

Can someone point out to me what I should be looking at? To me (a total NEWB in mechanics) they both look the same!

 

Kirk,
They're not the same. It is very subtle though. Closely follow the clip with your eyes in both pictures - upper pic shows clip in proper (and "different" groove).
Greg

 

You can't really see it in the picture, but when you pull your pads you'll see it right away if they're wrong. The Caliper piston has a groove cut in it where the pins on the backs of the pads slip into. Checked mine and re-did them yesterday. Took 5 min. per wheel. I found that bending the pins out a little bit helped to slide them onto the piston easier. Very easy thing to fix.

 

I had this EXACT same problem last summer... everyone here was very helpful. MY problem was that the back left pad was constantly popping OFF the groove of the piston.

Another hint: if you ever hear a high pitched squeal coming from the FRONT, check the heat/dust shield. If it rubs on or against the rotor, you will get one hell of a scary squealing sound from it. It's pliable enough to just bend it with gloved hands.

 

Thanks, guys! I did the brakes on my daughter's car last week and couldn't figure out why they were squealing and dragging a bit. Until I found this thread, I didn't realize the rear pads clipped into the piston. I got them clipped in this morning and they're nice and quiet. So is my daughter.
Thanks for the help!

 

Damn did the same thing. Do you guys think by the grace of god when I slid the brake assembly back onto the rotor that the clip magically went into the lip on the caliper????? lol Quick question also, I bled my brakes twice with ate super blue, and I still do not have that dealer brake pedal feel (still a little spongy). Do you think that maybe because I did not have the OBD II tool to put the car into abs/dsc service mode (per the bently manual) that that may be the cause??? help put my mind at ease!!!