I have a 99 300M and the passenger side makes a squealing noise not matter what speed I'm at, and hasn't gone away.... Also the passenger side rim gets really warm but the drivers side is perfectly fine, does anyone know what the problem is, and how to diagnose it?

 

check to make sure that the brake pads have been correctly installed

 

The Brake Pads are properly installed.

 

possible caliper locking up

 

I also thought it was a caliper locking up so I rebuilt the caliper but the noise continues.