I would suspect the cooling fan is not working properly. One of more of the cooling fans should run continuously when the A/C is on. If not the engine will overheat.
yes, as long as it has the same box syle body like an 84 silverado would have.
it all depends on the body style whether its the same or not
it could but you might need to trim the rear a little
Yes it will. Those 2 engines are the same. That would be a direct swop.
That would be a 4L60E.
That would be the 4L60E
That would be the 4L80E transmission.
It would have 3.73 gears in it
That would be the 4L80E transmission.
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I would say according to nada about 5-6 grand on a good day
Um... I would sure hope so since they are both 2003. But if you mean "will a bumper from a 03 silverado 1500 fit a 03 silverado 2500, (or the other way around)" I am not sure. It might, but the frame on the 2500 is bigger than that on a 1500.