I'm gettin my Greddy SP2 installed in a few days so I might as well fix my WS Y-pipe rattle. Now I have heard a couple solutions to my problem. I have two types of rattle. The first is a rattling sound at low speeds(like when parking)and when turning the wheel sharply(like when parallel parking). The second is more of a hollow, clunking sound, like the pipe is loose. This sound comes directly under the tranny and u can actually feel the grind. This happens at WOT, especially from a stop and when in lower gears or reverse. Now I have heard solutions regarding cutting or welding the heat shield, and rebolting the primary cat. Any suggestions from owners?

 

http://forums.maxima.org/showthread.php?t=310324