Brake Rattle with clunk/clank '07 XC70

[TheSaint]

Hi gang,

I was hoping you could help me do a bit of detective work.

So a few weeks ago I changed all 4 rotors and pads w/brembo rotors and (accidentally) brembo ceramic pads.

I up sized the front rotors and caliper brackets.

After install I experienced the symptoms that seemed to match incorrectly installed, or worn out anti-rattle clips. Brake feel that was spongier than before, and a rattle (especially from the Left Front).

Also, a sort of clunk/clank at slow speeds. I've taken a video of the front with the wheel off so you can see the install and also I videoed the clunk/clank and tried to capture the rattle sound as well.

I installed new rattle clips on the front, and it seemed to help (not eliminate) the rattle, but not the clunk.

Videos: , ,

I'd love to know your thoughts!

Best,

Bryce

[goldxc70]

Did you install the retaining springs correctly? Once, I did not and experienced symptoms similar to those you describe.

EDIT: On re-read, I see you moved away from stock so this post may be irrelevant.

[hoonk]

The click in your middle video when you go forward and touch the brakes is the sound of the brake pads moving in the brackets

Videos:

- take the caliper off and note the clearance between the caliper bracket and the pad backing plate on your aftermarket pads, there is too much clearance caused by too small brake pad backing plates or too large space in the caliper brackets. That can create a click when you reverse, brake, then forward, brake.

Might be making a rattling sound over bumps when driving also - test by driving over bumps that create the rattle a second time with brakes slightly depressed.

Solution - correct fitting brake pads or caliper brackets

[TheSaint]

Thanks for the reply! I THINK I installed them correctly. You can actually see how they are installed toward the end of the first video.

[TheSaint]

Thanks for the reply hoonk. Thats what I thought, and I could almost visualize the pads moving, and then getting stopped by the caliper. These are the pads that I got: https://www.fcpeuro.com/products/vol...70-xc70-eur794 which supposedly fit both 286mm and 305mm. The pads dont seem to rattle from bumps, but they do rattle/click at a consistent frequency that is tied to how fast I'm going. You can kind of hear it in the last video. The part that didn't totally make sense to me was that I cant see anything that seems out of tolerance, and I cant budge the pad with my hand. I've seen videos where people can wiggle the pad around, but I guess mine is tight enough to seem ok, but just off enough to make noise. Also, messing with it today it seems to be coming only from the drivers side...

[BillAileo]

The comment section on these on FCP includes one user with what appears to be a similar problem:

"I was a little surprised to discover that on occasion I have a squeaking sound coming from the front brakes when I casually approach a stop light or stop sign. The brake pads and rotors work fine but I guess I figured with what I feel are premium quality new parts (Brembo ceramic pads and Brembo rotors) I wouldn't experience a new sound that I have never had on the old 2002 Volvo V70 XC in almost 90K miles of driving. Started very shortly after brake pads and rotors replaced."

[vtl]

Did you accidentally bend dust shield(s)? Very easy to do unintentionally while working in that area. You can pry them away from brake rotor even with wheels on.

[hoonk]

I installed them correctly.

Yep - you are focused on the front - the rears can make noise also and it's real hard to tell which end of the car is making noise sometimes. The Factory rear pads have double sided adhesive on the outer pads to stick the pad to the caliper fingers - maybe to prevent movement? (and noise), inner pads have the metal cage that inserts into the caliper piston. )

[Xfingers]

Did you do some start and stop cycles to properly "bed in" the new brake pads with the new rotors? Just throwing things at the wall here...not sure how this would correct a rattling noise.

[billr99]

Yep - you are focused on the front - the rears can make noise also and it's real hard to tell which end of the car is making noise sometimes. The Factory rear pads have double sided adhesive on the outer pads to stick the pad to the caliper fingers - maybe to prevent movement? (and noise), inner pads have the metal cage that inserts into the caliper piston. )

As far as rattles at the rear, I've found that a lot of that is centred around the e-brakes. Too loose an adjustment or weak retaining springs can really cause those shoes to move around causing rattles. As far as the original post in regard to rattles in the front, it could be the anti-rattle springs or pads that are a bit too small dimensionally. Doesn't take much to allow the pads to shift within the caliper. But I would more suspect that the installation may have not tightened up the bolts sufficiently or the springs aren't right. If the OP is sure that it is associated with the brakes, there really isn't much more that could cause it as the number of bits involved are few.

Cheers,

Bill