Today we have a VY Commodore in Mermaid Waters. The owner is complaining of brake shudder and poor brake performance from his vehicle. The solution today is new front brakes for his Commodore.
Brake shudder can happen in any make of vehicle. It is a vibration felt though the steering wheel and brake pedal while braking. Commonly described as a pulsation in the pedal. It is due to an issue arising from the disc brake rotors. The rotors are affected by ‘disc thickness variation’ (DTV). This is were the rotors have worn unevenly. As the brakes are applied the brake pads do not contact evenly as there are flat spots. This can be caused by several reasons. The remedy is to either machine the rotors flat again (Depending on the condition of the rotors) or replace the rotors with new units. With parts becoming cheaper, some vehicles it is more economical to replace then machine. While these are been machined/replaced the technician will inspect and repair the rest of the brake system i.e. callipers slides, shims etc
Todays Commodore had new disc rotors and pads installed as the old rotors were not in a condition to machine, you can see the heavily rusted rotors in the pic below. Also from the rust marks you can see the brake pads have not been making full contact.
For more information about brake shuddering check out this Bendix article.