At what year did the intercooler change from the aluminum tanks to the plastic tanks? 04? 04.5? 05? Thanks.

 

If you are talking about the end caps changing (inlet/outlet assembly) going from aluminum to plastic that occurred on the 05 models. Obviously, the core remains aluminum for heat transfer/dissapation. My 04.5 is all metal.

 

Some of the early 50 trucks were also all metal, but they would be an 05 with a date code before jan 05.