What condition occurs when brake drums heat and expand, causing decreased effectiveness of slack adjusters?

Brake fade occurs when the brake drums heat up due to repeated application of the brakes, which causes them to expand. This expansion and subsequent heat buildup can reduce the friction between the brake pads and the drum surface, leading to a significant decrease in the effectiveness of the braking system. Consequently, the slack adjusters, which play a crucial role in maintaining proper brake pad contact with the drum, may also become less effective under these heated conditions. The metal components can undergo changes in their properties, resulting in increased stopping distance or a complete loss of braking power if not managed properly.

In summary, brake fade is specifically characterized by the loss of braking efficacy due to excessive heat generation, making it the correct choice in this scenario.