1FSTMAX

iTrader: (29)

Question what would cause a big brake kit to clunk when the car is rolling back? A friend of mine has a Big brake which consists of AP 4 piston calipers, 2pc rotors, and stainless steel lines. Any time the car is backed up it makes a clicking or clunking noise. It's like one clunk per revolution. The noise comes from the front, on both sides.. Everything is torqued to spec, and have double checked everything to make sure it's installed properly according to the installation guide. This noise only occurs when the car is going in reverse, not foward.

Any thoughts or ideas are welcomed.

Thank you,
Alfonso...

Maximum Velocity

iTrader: (3)

I too have noticed this and I'm not quite sure what causes it either. However, mine occurs under normal braking when coming down a pretty long (probably 1/5 mile) steep downgrade and I make a turn after my stop. I apply brakes periodically on the entire length and with the most pressure nearing the end of the length because the road is curvy and steep. It doesn't occur on level ground, going backward or anytime else. I notice mine predominantly from the driver's front and it goes away after about 5 seconds..probably 15 revolutions. I have the 4 POT Brembo Gran Turismo kit with the same specs as your friend's and I too have double checked everything. Other than under these conditions, which doesn't happen all that often the brakes perform just fine.

Jeff92se

iTrader: (82)

Maybe the pads are sliding back and hitting the back of the caliper holder assembly. Or if the rotors are slotted, maybe the slots are hitting the edge of the brake pad friction surface.

white m3 guy

iTrader: (6)

i think it is just when the pistons hit they hit hard i have a wilwood kit i have the same problem

Chunger

iTrader: (1)

It's probably the pads moving around in retainers... there's always a little bit of clearance... it happens when you change "directions" of the rotation and sometimes when you come to a complete stop (rarely)... nothing to really worry about.

Larrio

iTrader: (10)

i don't even have retainers for the pads on my brakes

maximum_rpm_nyc

happens on the wilwood kit all the time slotted and drilled rotors.
nothing to worry about.

HitManSE

iTrader: (1)

^Most likley whats happening^

Triple8Sol

iTrader: (29)

My Wilwood kit doesn't clunk... Besides the brake pads, could there some type of fitment issue with how the rotor itself is seated on the lug bolts?

Larrio

iTrader: (10)

how are your wilwood pads held in? My AP ones are just floating around with two tabs on the bottom of each side of the caliper to make sure it doesn't fall through

Chunger

iTrader: (1)

Depends on the Wilwood caliper but there is usually a "spring" guide/clip on both the leading and trailing edges of the pad backing as well as a bottom "tab" / upper pad hole for a guide...

Triple8Sol

iTrader: (29)

I have the standard Dynalite caliper, which is Wilwood's most common/popular choice. The pads are held in pretty much as Chunger described...