System PartsQuestion 17 of 60
Why should you NOT use the parking brakes if the brakes are very hot, such as after coming down a steep hill?
a.The knob may be too hot to touch
b.It will drain the air tanks
c.Hot brakes can be damaged, and the drum could contract and crack
d.The parking brakes will not hold on a downgrade
Explanation
If the brakes are very hot, applying and holding the parking brakes can damage them. On a very hot brake, the drum can contract as it cools around the applied shoes, which may crack the drum. Let the brakes cool before setting the parking brakes when possible.
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