I know some people have LT1 Fans on their 5.3L trucks but what do they do and what does it help? can you put LS1 fans on the 5.3? It might sound like a stupied question but at least i wont be a stupied *** not knowing what they do. right????? ------thanx

 

The stock clutch fan is a drag on your engine. By removing it replacing it with some electric ones, you free up about 7 ponies at the rear wheels.
This might help you.
http://james.jaguar.net/agreif/fans/fanstech.htm

 

Also LS1 and LT1 fans are the same fans. Only the shroud is a little different. And yes, you can put either on a truck.