5w20, My .02

[dallas]

Acording to oil manufacturers to call an oil SAE (Society of Automotive Engineers) a 30 weight it must be betwwen 9.3 to 12.5 centistokes at 100 celcius. I use an 5w30 thats near 9.3 at 100c. Im making a compromise between what Toyota originally spec's for our engines and what they now say as people want more mileage and they sell more fuel sucking Tundras. A 20 weight on the other hand is any oil between 5.6 to 9.3 centistokes at 100c. why would you take the chance and rely on tha additives to prevent wear like in a 5w20 when in a 5w30 you will rely on hydrodynamic lubrication( the oil itself).

Originally Posted by static808

i'm a little confused. i always thought the weights WERE the viscosity numbers. isnt a "light" 30 weight oil, by definition, NOT a 30 weight oil?? kinda like a 150 lb guy saying, "im a light 150 lbs." uhhh, you're either 150 or you're not. i would like it if you could further elaborate on "light" 30 weight oils, however, since if i CAN use a 30 weight oil that gives the efficiency benefits of a 20 weight oil, i'm all for it. currently using amsoil 0w-30, and planning on switching to 0w-20 as soon as i run out... thanks.

--B