Jason Godt of Grand Rapids said he was able to stop in time when the car in front of him suddenly braked for an ambulance approaching the intersection from the west on Robbins Road.
"The lady in a red Edge stopped on a green light," he said.
Behind him John Belasco of Muskegon was also able to stop, but he said it was a little frightening to look in the rear-view mirror and see a semi-track barreling down on him.
Semi driver Ben Scholten of Holland said, "the light was green. I didn't see everybody stopping for the ambulance."
He said his first thought was "I'm not going to stop. Take the median."
Scholten said if he hadn't hit the curb, he believes he would have missed the pickup truck.
Instead he sideswiped the truck with his cab and the trailer wheels caught the back of the pickup and pushed him into the truck in front of him.
Belasco said he was thankful for the semi driver's quick thinking.
"Believe me, it could have been a lot worse," he said.
Nobody was injured in the crash.