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What do the numbers on a brake drum mean?

What do the numbers on a brake drum mean?

Drums typically have cast on the outside of the drum printed “MAX. DIA.” which means maximum diameter. This is to let you know up to what point the drum can still be used. In my case 16.500 plus 0.010 equals 16.510, so this drum is well under the max diameter of 16.620 and still can be used.

What is the brake drum diameter?

260 mm
Drum outer diameter: 260 mm. Inner Brake Drum Height: 51 mm.

What is the maximum brake drum diameter?

Brake drums have a wear limit which is the maximum inside diameter the brake drum is allowed to be. 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. This is for your standard American trailer brake drum or drive axle drum.

What is the minimum brake lining thickness?

3.2 millimeters
3.2 millimeters is the bare minimum of thickness you want on your brake pads. Ideally, your pads will be over 12 millimeters in thickness. When you purchase new ones, you always want to measure them just to make sure they are the ideal size.

What is the biggest disadvantage of the drum brake system?

Drum brake disadvantages

  • Excessive heating can happen due to heavy braking, which then can cause the drum to distort, and thus cause vibration under braking.
  • Under hard braking, the diameter of the drum increases slightly due to thermal expansion, the driver must press the brake pedal farther.

When should drum brakes be replaced MM?

Most pads start their life with about 12 mm of friction material, and most mechanics suggest replacing them when they get to 3 or 4 mm. You should replace your car’s brake pads before the backing plate begins gouging out the brake rotors — a complication that can make the job even more expensive.

What is the minimum brake thickness allowed by DOT?

Title 49 CFR § 393.47(d)(2) states that the thickness of the brake lining and pads of non-steering axle brakes on an air braked commercial motor vehicle shall not be less than 6.4 mm (1/4 inch). If disc brakes are used, the minimum thickness is 3.2 mm (1/8 inch).

How long will 6mm brake pads last?

If the brake pads thinnest pad thickness is at 6mm then what the mechanic most likely recommends is to have the brakes checked in a about 1000-2000 miles to see if they will be needed then. Most brakes pads that are worn to 3mm is recommended for immediate replacement of the pads and resurface or replace the rotors.

Where can the maximum measurement be found for a drum?