Brake Drum: Testing and Inspection

1. Inspect and measure brake drum with Rotunda Brake Drum Micrometer 104-00046 or equivalent. Before making an inspection or measurement, remove grease, brake fluid or other contaminants from the brake drum using denatured alcohol.
2. Best shop practice requires measuring every brake drum with a brake drum micrometer regardless of visual inspection. The brake drum micrometer is set to the drum diameter and measures the amount and type of wear. Measure the diameter at various points of 45 degrees around the circumference and at the bottom of the deepest groove to determine if the brake drum requires replacement.