Ya i guess i worded it wrong. The viscosity rating is basically a way of saying how well the oil maintains its lubricating qualities over a range of temperature. The higher the number, the more extreme the temperatures it can maintain its lubrication.
I use synthetic and I have a lot of miles. It makes a hell of a difference. I used valvoline synthetic, but decided to switch to mobil 1 just recently. I switched mainly for the higher wieght 15-50. I’m back at 10-30 now, but I use to eat that shit for breakfast. I think it was just dripping from the drain plug. Napa gold filters are good, but I prefer the k&n cause I run my oil over 3000. I never used the flush stuff, but synthetic oil is suppose to have additives that eat away stuff with normal use just like the flush.
I use synthetic on my anus. :run: