I started hearing a "knocking" sound coming from the rear right of the car ONLY when I put on the brakes...any ideas on what might be the source of this problem? Everything on my rear axle,brakes, shock absorber, rods, bushes ect are new (4k km in total)

 

Most common issue with this type of sound is either worn out rear sway bar bushings and/or sway bar end links.

 

The sway bar bushings and sway bar end links are new :-(

 

It sounds like "pad knock" the tabs on the pads (guessing aftermarket pads?" are smaller than the originals or the hardware (stainless steel pad guides) wasn't replaced when the pads were put in.

 

Yeah the pad are aftermarket by Bosh, the anti whistle its still present, the pad guides are absent but it's normal, the etk can confirm this

 

Unless I'm mistaken, there are no pad guides on the Gen 1 MINI brakes...
I also have this phenomenon after recently changing my brakes all around (Akebono pads/Zimmerman rotors).

All suspension components, front and rear, have been recently replaced.

 

Sorry to confuse, just listing off the usual suspects.

Can you wiggle the pads forward and backwards against the slides once everything is together? If so there's your noise.

 

My pads are secure in place, no movements at all

 

Hmm interesting, do the caliper bushings feel nice and tight?

 

Nice and tight :-( no movement nothing, anyway the pins on the right side are shiny and clean (according to the workshop manual, the lubrification for the pins is prohibit)