Can you use a PS2 steering wheel on a PS3?

May be...

I have both PS2 and PS3 and i have a PS2 steering wheel and i was wondering if it would work on the PS3 if i buy one of those converters?

dont think so

No. The PS2 port is different from the PS3 one. The PS3 doesn't have controller ports, but it has USB ports to charge the controllers.

just buy an adaptor

I think u should try