I'm a newbie and in charge of my gf's 2003 GT Convertible with a few questions. We plan to most likely leave it stock, but is it better to use a KN air filter vs any replacement filter? How many miles between airfilter change? fuel filter change? Also, we are approaching 25k miles and I'm curious to what tires besides those stock GoodYears are recommended.
One more issue....The car runs perfect, but once in a while when we go to start it, it does one of those di di di di di (like when a starter is going bad) sounds. It's probably once-twice a week that it does it so is it worth showing the dealer and letting them tinker around?

 

Mine does the same thing, sometimes it takes a few cranks to start on occassion. Change your fuel filter every 30k miles or so, and any tire is better than the stock goodyears. I think Nitto's are a great tire for the price (not referring to the drag radials, the regular Nitto's), althought I have the dr's. And the K&N is a good filter, you wont have to ever buy another only clean it an oil it as often as you change a normal filter, and the extra couple hp is nice too

 

Nitto 555's....

I went from Kuhmos (Actually not an awful tire) 225/55/16 to the nitto 555's 245/40/18 and 275/35/18 and my car corners like CRAZY! My car fishtailes WAY less... The 18" tires are more expensive.... For cornering go 555's and put some D/R's on the back...

 

if you dont want to go with a k&n, then wix makes the best air/oil filters (i think anyway). And the starter thing just sounds like maybe a little mechanical glitch with the newer mustangs starters.

 

It's still under warranty isn't it? then take it to the dealer and have them see what'g going on before the warranty runs out.