first check your string gauges. i think super bulet 9s and slinky 9 are the same but they have different tension. fender usually have a lighter pull than slinkys.
second is your bridge floating (the back of the bridge off the body) or flush (agianst the body). if you reset it from floating to flush you may need new saddles (i did on mine at least but i didnt like the rolled fender saddles). next if your bridge is floating you might need to adjust the term springs under the back plate, the tension in your strings and the springs in the back need to be in equal balance otherwise the frets rattle everywhere.
if you not comfortable with all this stuff go to a local shop (as much as i love guitar center unless your best friend works there it doesnt count) and start talking to the people behind the counter the techs other guitar players, and remeber the only dumb question is the one you dont ask. tell the tech you get fert rattle tell them where it is and let them figure it out. it will cost you money but ask if you can watch ask questions, look up things on the net or go buy some books. guitar player repair guide by dan erlewine is a great book to get.
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