do i have to put polaris motor oil in a 4 stroke 425 magnum ,if not what do i need to use

 

Anything 0w-40 preferably Full synthetic.

 

I use Mobil 1 MX4T

 

Why does it need 0-40? What's wrong with 10-40?

 

wheres the photo ?

 

Nothing is wrong with using 10w40. The initial viscosity (measured at 40'c) is just a little thicker with the 10w vs 0w. The second number is most important. A 0w-40 and 10w-40 both have 40 weight operating temperature viscosity. The ow is thinner in ambient temperature, which can pour in lower temperatures. For summer, I recommend 10w40 because it is stronger for thermal breakdown. 10w40 is less volatile then ow40. Will give better protection when hot outside. However, if you are using a true chemically derived synthetic motor oil such as AMSOIL, both will work great. You can even mix the two!

irnieracing.com