Speed to Spare (1948)

Stunt driver Cliff Jordan takes a job with his old pal Jerry McGee, branch manager of an express trucking firm. Jerry is married to Mary, Cliff's former girl friend. Also working for Jerry is Pete Simmons, son of the owner Al Simmons, and office secretary Jane Chandler, who is Pete's sweetheart. Before long, Cliff has made enemies of Pusher Wilks, a trucker whose run he takes over, and also Pete, whose girl he is trying to take over. Pusher sabotages Cliff's rig at every opportunity causing several near-fatal accidents.