The most common cause of engine lockup is a lack of oil. Also, an engine overheating from lack of coolant can cause an engine to lock up.
When the engine can no longer rotate.
It could, any engine can "lock up" if not maintained properly.
No, only the compressor will lock up.
An engine can lock up on a number of reasons but mainly due to mechanical failure for example if the Timing belt snaps... etc...
either the timing belt broke or it ran out of oil
Depends on what caused the engine to lock up. Most of the time a locked up engine is very serious and will require disassembly.
was there oil in it?
does you truck have drum brakes in the back
Lock up, No but a bad crank sensor will prevent the engine from starting.
Major engine failure?