The 4.0 is just a noisy engine. Check out "The Car Care Nut" on You*ube, he's a Toyota mechanic with his own shop.
Overseas the 4.0 is approved for up to 20w50, I'm currently using 5w30 and it has quieted down a lot. (this is in the 2013 FJ, same engine, but I also used 30 in the 2015 'Runner...