This is probably old, but I heard it from a friend for the first time
a couple of days ago:

Two Kentuckians [or your favorite ethnic/social group] were driving
a semi down a road when they came to a viaduct. The sign said 10 feet
zero inches, so they got out to measure their truck. Unfortunately,
the truck was just over 12 feet high. They didnt know what to do,
when finally one of them looked both directions and said, I dont
see any cops, lets go for it!