Is my 50,000 mile '11 G37X sedan pinging near the shifts? I only run premium (10% ethanol). It only happens at WOT and near redline. Next fill up I'm going to try 3-4 gallons of 99 octane no lead to see if it goes away. I've searched, and haven't seen much on the subject.

 

 

Thank you for the reply. I did spend plenty of time searching with no results. After searching exhaust rattle there were lots of results. It's pretty loud in the cab when it happens. There's even a TSB on converter shields rattling. Exhaust rattles seem very common on Nissan's. Though this rattle is very different than what i usually hear, I'm pretty sure you are correct at this point. For sure detonation does happen at WOT. It's just more audible at lower engine RPM's. I would think that the OE's use pretty conservative WOT timing along with detonation sensors to limit warranty claims.