Vehicle InspectionQuestion 20 of 120
You notice oil or grease on the outside of a brake drum during your walkaround. Why does this matter?
a.It causes the drum to rust faster
b.Contamination on the friction surfaces greatly reduces braking power
c.It makes the wheel bearings spin too freely
d.It prevents the ABS light from working
Explanation
Oil or grease on brake linings and drums destroys the friction the brake depends on, so stopping distance increases sharply and braking can become uneven. Rust, bearing speed, and the ABS lamp are unrelated to contaminated friction surfaces.
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