Which of the following valve(s) is designed to reduce rear wheel lock-up to balance a disc/drum system?

A) pressure differential valve
B) proportioning valve
C) metering valve
D) all of the above

Proportioning Valve

A valve in a vehicle's brake system that modulates the pressure to the rear brakes to prevent them from locking up during braking.

Rear Wheel Lock-up

A dangerous condition where the rear wheels of a vehicle cease to rotate while in motion, often leading to loss of control.

Disc/drum System

A braking system combining both disc and drum brake technologies, typically with discs on the front wheels and drums on the rear.