Could also be: whining noise coming from the secondary timing chain
system. Nissan V6 4.0L engines had the same issue, Nissan launched a bulletin to fix the issue.
YouTube...
It probably is your oil filter or the oil cooler. Read below...
I have the similar 2012 T4R SR5 V6 4.0L started doing it right after I booted the truck one morning, engine was not fully warmed up yet. (my guess is the oil pressure rushed higher when engine was cold, collapsed or clogged part of...