Originally Posted by iwasgointo

Just yesterday morning (Saturday), I changed the oil of my 2009 370Z using the Amsoil top of the line Signature Series oil. The weight is 0w30 which is what Amsoil recommends for this engine. The car has 7800 miles on it. I drove it around for a short time and everything seemed fine.

Well, today I got up early and drove 32 miles to an excellent twisty road that's about 8 miles long and a favorite of motorcyclists. After doing one pass where the car is kept mostly in 3rd gear and the rpm's stay in the 4 to 5k range, I pulled over and popped the hood and noticed a louder than usual valve clicking noise. I then stepped back next to the drivers doors and the clicking was even louder.

I then did another pass on the twisty road and headed home. When I got home the car sounded normal and a couple of hours later I started the car and everything seemed fine.

I know the Amsoil is a very thin oil, but is supposed to offer superb protection against wear at any speed.

I like to drive like this every now and then and I wonder if I should add a viscosity increasing additive such as STP? My thought is the Amsoil is a bit too thin for this particular engine.