Some vehicles with disc brakes have wide-open rims and easily accessible and visual calipers to allow you to look in at the pads to monitor their thickness. Of course, you can't see the inboard pad, so you're getting only half the job done. And just because the visual outboard pad has plenty of friction material doesn't always mean the inboard pad does as well. Some vehicles do not even offer the luxury of viewing the outboard pad without removing the wheel, and for other vehicles, you must remove the caliper to see the wear on the pads.
Instructions
- 1
Park the vehicle on a flat, paved surface. Apply the parking brake if you're checking the front brake pads, but do not apply it if you're checking the rear pads. Many rear disc brake vehicles incorporate the caliper as part of the braking system, and if you apply the parking brake, you may not be able to remove the caliper to inspect the pads.
2Place a wheel chock behind one of the rear tires if you're checking the front pads or in front of one of the front tires if you're checking the rear pads.
3Break the lug nuts loose on both left and right tires of the axle you're inspecting the pads on using a breaker bar and a socket. Lift the axle, one side at a time, with the floor jack and place the jack stand(s) in a safe and secure place. You can inspect one side at a time or lift both sides to elevate the entire axle. Remove the lug nuts and the wheel.
4Look at the caliper to see if there is a porthole in the front housing of it. On some vehicles this will give you a visual of the pad from the side. Compare the distance of the backing plate of the pad to the surface of the rotor. Some vehicles may have a metal hardware clip preventing you from inspecting the pads this way. And some may not even have a porthole. No matter if the vehicle does or does not, the best way to inspect the pads for sure is to remove the caliper.
5Locate the two caliper bolts and remove them with the ratchet and a socket. Sometimes one bolt is different from the other one, so pay attention to which is the upper and lower as you remove them.
6Pry the caliper off the pads and rotors (and in some cases, the pads will be clipped directly to the caliper as you pry it off) using the flathead screwdriver. Remove the pads from the caliper or the caliper anchor, and again, in the event you're just inspecting them and not replacing them, incorporate a relationship with each pad and its position in the anchor or caliper to replace it in the same manner you removed it.
7Determine the wear of each pad. Things to look for are that the pads are wearing evenly with one another and evenly across the plain of the individual pad itself. Uneven or angled wear on a single pad could mean the pad is getting cocked or stuck in the anchor. Uneven wear between the two pads could mean one pad isn't sliding well or is stuck in the anchor. The thickness of the friction material of the pads that are wearing evenly and properly is equally important. Depending on driving conditions and braking habits, you want a good thickness of the pad.
8Use the depth gauge to measure the thickness of the pad in 1/32-inch increments (common U.S. measurement). Place the depth gauge stop on the friction material of the pad and depress the lever to the backing plate of the pad to get the reading.
