Brake Drum Measurement

Inside finished diameter b.

Brake drum measurement. Dust shield recess diameter if applicable j. 3 7 out of 5 stars 17. The maximum diameter of a brake drum is listed 11. Brake drums are cast iron or iron lined aluminum.

Actual brake drum dimensions see figure below a. 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. The drums do wear however and can only get to a certain measurement called discard in order to remain effective. This requires a good eye and also some experience.

Overall diameter of drum i. M measurement of drum c cut measurement d discard value as determined by manufacturer specifications 1. Also a cast iron drum should ring like a bell when struck. The cast iron inner linings are harder and more brittle than the area around the hub and lug holes.

Make and number of axle 3. It is not recommended to strike the outer area of the drum where the shoes ride. 11 990 2c 12 030 2. If the drums aren t worn past legal tolerances 0 060 of an inch they can be reground or turned rather than replaced.

More buying choices 78 60 17 new offers 150mm 6 digital brake disc drum caliper gauge digital micrometer. Manufacturer s brake drum number 4. The maximum diameter of a brake drum is listed as 12 030 inches. The normal lifespan of brake pads is between 30 000 35 000 miles.

The drum measures 11 990 inches. Brake drum inspection and measurements. 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. Look at the rest of your brakes which are still attached to the brake backing plate.

Drum type see page 3 5. Wheel or hub number 2. However it can be even more or less depending on the car s make and model driving habit and road conditions. Information required for drums not listed in this catalog.

What size cut can be made before the drum must be discarded. Transcript brake drums have a wear limit which is the maximum inside diameter the brake drum is allowed to be. 5 0 out of 5 stars 1. If you need new drums have a professional install them for you because the brake shoes must be adjusted to fit.

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.