I remembered another GM engineering plum:
The door hinge pins on S10's whose bushings crack and fall out without regular lubrication (think monthly in dusty environments). The pins then wear into the hinge bracket which is welded to the cab.
The fix is welding the holes up & redrilling them, which is not an easy operation according to a friend of mine who owns a body shop.
'7? Benelli 650S, '80 BMW R100 RS, '93 Ducati 900 SS, '07 KTM 990 Adventure