Provided herein is an adjustable pedal assembly for a vehicle for operating a push rod of a brake system, for example. The assembly includes an activation link connected via a pivot member to an elongated lever structure of the pedal arm, a link member for connection to the push rod to activate the brake system that is operatively connected to the activation link, and an adjustable slide pin for moving a pivot axis of the elongated lever structure between a first pivot position and a second pivot position. The pedal arm and pedal plate are thus moved between a first position and a second position, while maintaining a substantially constant ratio between each of the positions.