It could happen for a number of reasons - which of those reasons fits your case is impossible to tell without doing a proper diagnosis of the cooling system.
Distributor cap could have a hair line crack in it.
low oil low radiatio flued or the thermistat
It can help prevent damage on your truck bed. However depending on the weather and the quality of the cover, it could damage the cover itself and from there cause damage to your truck bed.
Engine may overheat and seize
Check the thermostat or the radiator. The thermostat could be sticking or the radiator could be plugged.
Check the radiator hose for weakness or it could possibly be the wrong hose.
It will overheat at idle.It will overheat at idle.
most definetly can casue overheating and probaly cook the belt too
There could be a number of reasons why your truck will not shift properly. There could be something wrong with your clutch or transmission.
trottle control module
it could be the window