Grocery thrower has run shuttles off and on for a while now, he'd be best to explain more but basically you're driving empties from the yard to the main warehouse at night and returning with loaded trailers for the next day's deliveries.
Working conditions depend 100% on which warehouse you're working out of. Some are great, some good, some bad and others downright horrible just depends on local management. Generally life in a shuttle yard should be more laid back than working onsite, running shuttles overnight should be even more laid back than that. Fewer people hanging over your shoulder.
Pay will also vary depending on location, whether or not they're Union, etc. I know the Chicago drivers are all hourly and make really good money (29-ish/hr). Don't know how far outside the city they go though, this yard may belong to one of the WI warehouses. If they're non Union (I don't believe they are) benefits costs will be much higher, no pension, etc. and again pay depends on location and how much they see fit to give you, whether it's 4 or 5 days/week etc. Ask them lots of questions.
