How did no one get killed making this movie?

Every time they took a hard corner in that truck, especially with John Wayne in that fender seat, I cringed waiting for it to roll over. Funny how in the trivia, John Wayne said he was afraid of the same thing. Between that and some of the jumps they took, it's a wonder one of those vehicles, especially the jeep, didn't nose into the ground and do an end-over and get someone killed that way.