I noticed that my 4 wheeler has 50 hours on it but only 465 miles. That tells me that it does a lot of lower speed driving. My brother's RZR says to service at 25 hours. I'm thinking I might start  to do it by hours no matter how many miles it's been. If the motor is running than the hours are counting whether your putting miles on it or not so I feel like it's a more accurate way to service.

i have always seviced all my off road atv`s , dirt bikes etc by hours and how severe the ride was.

i have always seviced all my off road atv`s , dirt bikes etc by hours and how severe the ride was.

What is your normal hour limit for service?

my 600 touring has 130 miles and about 40 hrs . it see`s a lot of slow woods and idling. its on its third oil change. so about 20 hrs on each service. normal riding i change thee oil every couple hundred miles.

My 500 has 50.5 hours and 4** miles on it. I did the first oil change at 10 hours and 1** miles. Then the second one at 25 hours and around 250 miles ish. Now I'm doing the third one at 50.5 hours and I'm changing the front and rear differentials too. I'm torn now over whether to fill to spill or fill to the manuals specs. I did my side x side to the manual specs and only put 400ml in the rear. Fill to spill is the normal but who knows. I see videos on YouTube that show filling until it comes out the hole by some big name shops. I'm not sure it even matters.

[2015 Z Force 800 53/Trail EPS]

My 500 has 50.5 hours and 4** miles on it. I did the first oil change at 10 hours and 1** miles. Then the second one at 25 hours and around 250 miles ish. Now I'm doing the third one at 50.5 hours and I'm changing the front and rear differentials too. I'm torn now over whether to fill to spill or fill to the manuals specs. I did my side x side to the manual specs and only put 400ml in the rear. Fill to spill is the normal but who knows. I see videos on YouTube that show filling until it comes out the hole by some big name shops. I'm not sure it even matters.

It matters on CFM. Filling like we do on all others will result in it coming out the vent when hot and talk about stink... Also its harder on the seals and some start leaking and don't stop even if lowered...and they run hotter.. if you can believe it. Go a little more then the book..maybe an ounce, but no more.

I drained the rear last night. I'll fill it up tonight by the book. 230ml front and 250ml rear. Should be able to do both 4 wheelers off of one quart. Was going to use this oil because I already have it.

Finished up the diff services tonight. 230ml front and 250ml rear. I ended up using Lucas 80w90 because I found it on the shelf in my garage and it seemed better than the Napa. Nothing scientific just a hunch that it was better product. Should be good for the rest of the riding season especially since the wife favors the side by side over the 4 wheelers when we ride.