I know a New England Motor Freight driver in my area.
he was on his way back to his terminal after getting his route finished.
He was northbound on one of our expressways doing about 60 mph.
Suddenly his left front wheel broke off the spindel,and as he came to rest in the ditch on his right.
he helplessly saw his wheel,bounce over the center grassy section seperating the north,and southbound lanes.
It jumped up high and came down into the windsheld of a car going southbound instanly killing the driver.
This has got to be about 4,or 5 years ago.
There was a long investigation that found no fault to the driver,or the trucking company.
Just a freak accident.
You can take care of your equipment on a regular basis but parts don't always last forever.