Yea done quite a bit of reading on the subject of oil filters, in fact which brands are supposed to be the best. And actually I think my owners manual says first one at 500 miles and then at 12,000 mile intervals. At least I think that is what it says. Kinda having a hard time grasping that one and don't think I will follow the book on that one. One of the main reasons for this recomendation is the environment that these sleds are in. Even though it is cold they are not exposed to the dust, and unlike the motorcycle division you also don't have to worry about wet clutchs. Because if you really look at it in the big picture alot of guys are saying they go 4 stroke to save on all that oil for a 2 stroke but if you buy Synthetic and a good filter it equals a couple of gallons of 2 stroke anyways. (if not more) I just bought 6 quarts of mobile 1 synthetic. (3.5 for the sled and the rest in case it uses any) and a filter. Oil was $36 and filter was $15. And this is not Yammy brand. That would have been a little more. I just bought my 2 stroke oil for the year bulk from the dealer and it was $20 a gallon. And 2 gallons of 2 stroke usually will last an average person one season on one sled.