Driveshaft fell off

So even though it was vibrating bad you were driving it down the hwy?? Makes no sense at all. You'll be lucky if it didn't break off all the bolts in the yoke and bend the driveshaft. Good thing it didn't go through someone's windshield and kill them.

Ignorance is bliss and sometimes you lead a charmed life.
One of my first truck driving jobs years ago was in a 10 yard tamdem axle dump, and pulling a 6 yard pup to boot. It was an old and very used up 318 diesel Jimmy. Doing all of 25 miles an hour in the outside lane of bumper to bumper 8 o'clock rush hour freeway traffic one morning I had one of the drivelines let go and fling itself accross all four lanes of traffic. It didn't hit a damn thing except the concrete divider barrier separating inbound from outbound traffic.
Yup, sometimes you lead a charmed life.