Was told by the dealer not to use synthetic oil on the G37? anybody else using synthetic oil?

 

Manuals tell you use the special Nissan Ester oil. Go to a infinti dealer, and you might get the ester oil, you might get the cheap dino they give out by the gallon. The ester oil was added as manual entry a few years back when a number of people reported some 'valve noise'. Not everyone did, but some did. Go search through the oil threads, and you'll see the variety of what people use. Be sure to compare what 'NEW' people use, and then see what people who now have 15-20 thousand miles on the vehicles use. And go back to see what people who first reported using one type of oil, if they're still using the same oil, and if they've had their vehicle long enough to give their statements any merit. [e.g. someone who's only had their car for 3 thousand miles claiming brand X is the best thing ever doesn't mean much compared to someone who's had their G37 and previous G35 go through 30-50 thousand miles with a particular brand of OIL. And those comments mean less than someone who's actually had a vehicle last 100+K. Though I doubt you'll find many people who'll still have a G37 that long, as they'll likely swap it for another young toy in 3-5 years]