I applied in-person. The process took 3 months. I interviewed at Caterpillar (Peoria, IL) in Aug 2016
Interview
I was a summer intern and they gave all summer interns the opportunity to interview at the end of the internship. The interview was three hours long and it consisted of three 1-hour interviews with three different people. I didn't hear back for about three months.
Interview questions [1]
Question 1
They exclusively use STAR questions. Many of them are about your experience with working with others. They want to see that you are a team-player and work well with others. i.e., "Tell me about a time when a teammate didn't do what you asked of them. What did you do, and what was the end result?"