ASVAB (Armed Services Vocational Aptitude Battery)Auto and Shop Information (AS)Hard
An automotive technician is performing a brake inspection and notices excessive scoring and grooves on the brake rotors. The brake pads are also significantly worn. What is the most appropriate course of action to ensure proper braking performance and safety?
- AReplace only the brake rotors, as the pads might still have some life.
- BReplace only the brake pads, as they are the primary wear item.
- CReplace the brake pads, rotors, and calipers.
- DResurface the brake rotors and replace the brake pads.
Show answer & explanationAnswer & explanation
Correct answer: D. Resurface the brake rotors and replace the brake pads.
Excessive scoring on rotors indicates they are past their service limit for simply replacing pads. While calipers are usually fine unless leaking or seizing, the rotors need to be either resurfaced (if enough material remains) or replaced, along with new pads, to ensure proper pad seating and effective braking.
Why the other options are wrong
- A. Replacing only rotors and keeping worn pads is illogical and unsafe; new pads are always required when rotors are serviced or replaced to ensure proper bedding and optimal braking.
- B. Replacing only pads on scored rotors will lead to rapid wear of the new pads and poor braking performance.
- C. Replacing calipers is usually unnecessary unless they are faulty (e.g., seizing, leaking). This is an excessive and costly step if only pads and rotors are worn.
Brake Rotor Resurfacing
The process of machining a brake rotor's surface to remove imperfections like scoring, warpage, or rust, providing a smooth surface for new pads.
- Done if rotor thickness is above minimum specification.
- Removes grooves and ensures flatness.
- Always done in conjunction with new brake pads.
Memory trick: Pads and rotors work as a pair, neglect one and safety's rare.