How to Adjust the Height of a Brake Pedalby KevinM
The proper adjustment of the brake pedal is necessary to give the driver maximum control over the brakes. An imporperly adjusted pedal can undermine the driver's confidence and concentration, creating a potentially dangerous situation. The brake pedal height is the most common pedal adjustment, and is easy to do yourself if you know how.
Park the car on level ground and set the parking brake. Move the driver's seat as far back as it will go.
Push on the brake pedal with your fingers and note how much free play there is in the pedal. It should move about 1/8 to 1/4 of an inch before it starts to engage the brakes. If the pedal has no free play then it is constantly engaging the brakes, causing them to drag and wear prematurely. If there is too much play the brakes will feel soft and mushy.
Slip under the dashboard on the drivers side and look up at the brake pedal. Near the top of the brake pedal arm you will see a threaded pushrod that comes out of a rubber boot or metal housing on the front wall of the car and attaches to the back of the brake pedal arm. There is a locknut on the pushrod at the brake pedal end, and usually at the end near the front wall as well. Place a visible dot on the pushrod roughly at the middle between the locknuts.
Loosen the locknuts at both ends of the pushrod. Be careful not to rotate the pushrod when loosening the locknuts. You can visually verify if the pushrod is turning by keeping an eye on the dot that you put there previously. If the pushrod does move a little return it to its original position using the dot as a reference.
Rotate the pushrod clockwise to increase pedal height by moving the brake pedal out and upwards. Rotate the pushrod counterclockwise to decrease pedal height. The rod can be rotated by hand, or with pliers if necessary. As pedal height is increased the free-play will increase as well, so be careful not to increase the height too much. As pedal height is decreased the mechanism will reach a point where the pedal is no longer being lowered but the pushrod is being pulled out instead. This is effectively moving the master cylinder piston from its normal rest position, and brake drag will result. You can tell how far you have adjusted the pushrod by checking the position of the dot.
When the pedal is adjusted to your satisfaction, carefully tighten both locknuts.