Life span of a VQ37?

2011 Nismo#91

A well maintained engine and not abused engine will last hundreds of thousands of miles. The rubber and plastics will break down before any mechanical failure baring any defects missed at manufacture.
My family drives a lot of highway miles and usually get over 200k miles with only one mechanical issues from the engine on about 7 cars. The one engine failure was in a 79 Camaro where a push rod broke. Everything is standard maintenance and 3k ish oil changes.
This is the main reason why so many manufacturers have been increasing their power train warranties.