Exhaust resonance
 

I have a new 07 GT with stock exhaust. There's some fairly significant exhaust resonance around 1200 RPM, which is about 35 MPH where a lot my residential street driving occurs. Anyone else experienced this?

downshift = problem solved.

That seems like a really low RPM for resonance, I recall reading an article in one of the rags when the '05 first came out that talked in depth about the technology that went into the exhaust tone, my dad's '05 has a stock exhaust and I didn't notice it (and I'm a Flowmaster resonance Junkie.. I love it)

simple and effective.