I use Amsoil in everything I own and have for a long time and never had any problems with it at all. When I bought my 06 500efi I put Amsoil 0W-40 in it and a Amsoil filter. With about 28 hours on the oil change the motor got really noisy, so I changed back to the Polaris oil and filter for an oil change to see if it made a difference and the Polaris oil made it alot quieter. The Polaris oil keeps the motor quiet until about 40 hours and then I change the oil and filter. I asked my dealer about this and he said that the Amsoil breaks down quicker than the Polaris oil. I told the dealer he didn't know what he was talking about. I personally think that their must be some additives in the Polaris oil that are specifically designed for the 500 engines, because I had a 05 700efi and put 300 hours and 3000 miles on it and and used Amsoil 0W-40 and it ran and sounded perfect from day one. Anyway if something does happen to my motor under warranty, they can't really question it if I use the Polaris oil and filter.

 

So some of you guys are running regular automobile oil in your ATV's???

DOn't Polaris's have to have "wet clutch" oil?????

 

I only use Spectro Synthetic in every motorcycle I have ever owned and I will never use anything but. They only make oils specifically for motorcycles and atv/pwc's. They also make it themselves and don't just relable another brand.