Brake Drum Measurement

Brake pads sit between the brake shoe and the brake drum and they are crucial to the brake system of a vehicle brake thickness also plays an essential role in engine s proper operation and also for road safety.

Brake drum measurement. What size cut can be made before the drum must be discarded. Actual brake drum dimensions see figure below a. M measurement of drum c cut measurement d discard value as determined by manufacturer specifications 1. This number is often cast on the outside of the drum it s allowed to be 422 1 millimeters or sixteen point six two inches.

11 990 2c 12 030 2. The maximum diameter of a brake drum is listed as 12 030 inches. This requires a good eye and also some experience. The drum measures 11 990 inches.

Look at the rest of your brakes which are still attached to the brake backing plate. Lave ample space at the top like in the diagram and use a measuring tape to see if the brake band wraps nicely around a 4 3 16 4 3 4 or a 6 inch drum brake. Overall diameter of drum i. An over sized or thin drum will compromise the effective braking power of the drum brakes and can also be dangerous if the drum disintegrates.

The drums do wear however and can only get to a certain measurement called discard in order to remain effective. If you need new drums have a professional install them for you because the brake shoes must be adjusted to fit. However it can be even more or less depending on the car s make and model driving habit and road conditions. It is not recommended to strike the outer area of the drum where the shoes ride.

More buying choices 78 60 17 new offers 150mm 6 digital brake disc drum caliper gauge digital micrometer. Manufacturer s brake drum number 4. Brake drum inspection and measurements. Wheel or hub number 2.

Information required for drums not listed in this catalog. Inside finished diameter b. The cast iron inner linings are harder and more brittle than the area around the hub and lug holes. Only 9 left in stock order soon.

The maximum diameter of a brake drum is listed 11. If the drums aren t worn past legal tolerances 0 060 of an inch they can be reground or turned rather than replaced. Brake drum and rotor measuring kit w caliper. 5 0 out of 5 stars 1.

The normal lifespan of brake pads is between 30 000 35 000 miles. Brake drums are cast iron or iron lined aluminum. Make and number of axle 3. Drum type see page 3 5.

3 7 out of 5 stars 17.