I know there is a lot of discussion between oils and all, I’ve read up on basically every thread about oil and narrowed it down to Royal Purple and Rotella T6.

My question is Rotella T6 is a diesel engine oil (diesel = rather low rpms), our engines constantly run around 4000-6000 rpm, would this diesel oil still be a good choice?

I’m specific about maintenance and want to find the best oil for my quad, I’ll be running 5w40 in the summer and 0w40 in the winter (it gets really cold here and I plow a lot).

Over here in Canada a jug of Rotella is $50 for 5L (1.3 gallons) and 5L of Royal Purple is about the same.

Any advice is appreciated, if there’s any other oils I should look for I’m open for ideas… Amsoil is pretty much non-existent where I am, even Canadian Tire doesn’t seem to sell it.

Thanks