trucks used in the salt-belt states can have accumulated corrosion in the hinges of the rear doors. if the vehicles also have misaligned door latches and strikers, it is possible to close the doors in a "false latch" condition.
due to insufficient clearance between a bolt that fixes the heater to the vehicle body and a fuel delivery pipe and between a rear heater hose clip, use under servere conditions could cause pipe rupture and fuel leakage.