[VTEC]TL

I have a 2007 TL base 5AT. I noticed that if I floor the car in 3rd, when the tranny shifts from 3rd to 4th, it shifts fairly hard, and I hear a squeak/chirp from what sounds like the passenger front side of the car. It happens in SS mode, but also sometimes in auto(sometimes it shifts smoth enough in auto and I don't hear anything). It almost sounds like a quieter version of an HKS blow-off valve that I had on my WRX. It's not the tires, so I was wondering what it could be.