Based on the context and the answer, generate a question. 

Context: So I did . Then , at the bottom of the Coquihalla Highway , there was an East Indian fellow who got out of his truck scratching his head at the great plumes of smoke billowing out from the wheels of his trailer . Looks like he got an expensive lesson on why you 're not supposed to ride the brakes going down a hill .. I do n't feel sorry for him , but I am very glad nobody was hurt ... The rest of the trip to Van went without incident .

Answer:

He drove the truck in a gear that was too high down the slope .



What is the reason great plumes of smoke billowing out from the wheels of his trailer ?