I have an 03 GT and when I am driving slow over broken pavement I can hear a clunking/knocking sound coming from mostly the passenger side front strut area. Sounds louder if someone is sitting on the passenger seat with the extra weight. The noise goes away a higher speeds, just does it when going slow over bumps. More annoying than anything else. Could the strut plates be going bad? I have 40000 miles.

welcome to AF.

Yes it could be the strut mount(upper plate, bearing plate) or it could be a broken spring, busted suspension part.
Kinda hard to say with out inspecting carefully, which I'd recommend getting it looked at for saftey's sake.

Ok thanks! Another thing is that when it gets really hot under the hood like on a hot day its more noticable sound than when cold.