Not a mechanic, but I stayed at holiday inn....never mind...I was around the shop a lot because I drove a tractor that had a lot of stuff wrong with it. There are tractor mechanics, package car mechanics and trailer mechanics where I work. There are times when you have to be a jack of all trades. Package cars run during the day. tractor/trailers run 24/7. If you are on duty, you may be required to change a mudflap or a taillight, no matter what your specialty. As a mechanic, I believe just about all your time is reserved doing PMI's (preventative Maintenance Inspections) you will have a certain # of the fleet assigned to you, and your name comes up if one of those have a breakdown. Day or night jobs, depending on seniority. I believe UPS launders your unis. You get a tool allowance as well. Good luck to you.