What's the hardest part of driving a big rig?  What can drivers see that you don't know about? Is it harder to haul flammable material or a trailer full of cows?

Dave Keim teaches students the finer points of truck driving, including parallel parking with a 53-foot trailer.  Keim fills us in on what truckers want you to know while they are on the road... and what they don't tell you about bathroom breaks.

View the transcript here.