Which oil is best

If you search around the internet for the best oil I think you will come to a conclusion that marketing has pretty much taken over that question. However when it comes to your Fourtrax you are still in question about what type of oil is best.

The answer is really simple although a lot of oil distributors do not want you to know this. It can be found by looking in a factory service manual. I am not even suggesting using the brand of oil listed in the manual though.

While recommendations on viscosity can change with temperature for general use it is recommended that you use an API SF OR SG 10W40 motor oil. So which brand? It is the authors opinion that the brand of oil is not nearly as important as meeting the API specifications and manufacture requirements. Beyond that most oil companies get their base stocks from the same place and just change their additive package.

If you are looking for a good oil I would suggest going to your local auto parts store and look for ATV specific oil meeting the SF or SG API specifications that is rated for use with a wet clutch. Motorcycle oil of the same viscosity rated for a wet clutch and meeting the specifications listed in the service manual will work equally as well.

Do not run out and buy the slickest synthetic oil in 10W40 that you can find and dump it in. First off it absolutely has to be rated for a wet clutch and it has to meet the SF and SG specifications. A lot of these oil companies hide behind the Magnuson Ferguson act mis-representing the reason for this act in it's entirety. The act states that if you modify a vehicle under warranty and it fails due to something unrelated to the modification the manufacture must cover it since it must in fact be a defect. However oil companies will lead you to believe they have not met API testing because the manufacture of your atv is just pulling the wool over your eyes. They aren't though. Honda knew well what to put in their machinery and putting the wrong type of oil in your atv will quickly lead to a slipping clutch.

Your atv does not need additives, it won't benefit from a different type of oil than specified, and will suffer clutch issues if you do not use the appropriate type of oil.

The author believes that frequent oil changes, always replacing the filter at changes, and maintaining proper oil temperature will always be far more important than brand names. Snake oils are just that, snake oil. The key to a good running, long lasting engine will always be appropriate maintenance.