Knocking in 02 QX4

[gskover]

Hi,
I'm new to the forum and followed the instructions to replace the rotors and brakes in a 2002 QX4. All went well until the test drive. When braking there is an obvious knock on the passenger side until the car stops. There is no knock when the wheel is spinning free. I rechecked everything and all the bolts are tight. Any idea of what it could be and how to fix it?
thx,
Greg

[Towncivilian]

Welcome to NICO.

Did you torque all the bolts to spec? See BR-23. Some bolts require relatively high torque (the caliper bracket bolts for example) and if you just tighten it by feel, that may not be sufficient.

Were the slide pins and pad shims (if applicable to the pads you used) lubricated with proper brake grease?

[gskover]

Thx,
I did not use a torque wrench to tighten the caliper bolts but I will now!

[gskover]

Actually bolts were tighter than recommended so I adjusted to 130 ft-lbs and it still knocks on braking

[Towncivilian]

Did you reverse the inner and outer pads by any chance? Sometimes brake pads have specific inner/outer pads.

Please answer my previous question about slide pin and shim lubrication. Were the rotors sufficiently cleaned/degreased prior to install? Are there any deposits on the rotor surface? Perhaps try sanding the rotor surface.

[gskover]

I greased the ears of the pads but the shims were attached to the new pads so I didnt grease them. I did the same thing on both sides but only the passenger side is knocking. One "clunk" per rotation of the wheel.

[laider]

What kind of rotors- slotted, drilled, solid? "Clunk" or "chatter"?

[gskover]

The rotors are solid, purchased from Autozone. The sound is a loud knock once per wheel rotation.

[Pathfound49]

I had that knocking sound after putting on an out of round brake drum. Had the drum turned by a machine shop to fix it. A slight high spot on the rotor(even a new one can have issues) might be causing your sound as well.

[gskover]

Thx for your insight. Never thought that a new rotor would be defective but after reading your post I took off the new rotor and put back on the old rotor and the sound disappeared. I took the rotor back and got a replacement, installed it and the sound was gone. What a relief!

[Pathfound49]

Happy to help.