My owners manual requires 10W-40. Most automotive full synthetics don't come in that particular weight. Anyone know what the closest equivilent full synth viscosity is? I'd prefer Mobil or Valvoline. I guess I've never really understood the whole xW-X thing.... Obviously the in single grades the higher the number the thicker the oil, but where does the "w" come in... Also, why can't they just make the full synths in the same weights?
BTW I called the Mobil guy and all they would tell me is to use the motorcycle oil form of full synth Mobil. Not very helpful.....

 

DO NOT use automotive oils in an ATV.

If you want a full synthetic use Amsoil or something.

 

This is correct for your KFX-400 and Warrior, but not for quads with a CVT such as the Brute or Prairie. The Brute and Prairie do not have a wet clutch, therefore using automotive oil is fine. In fact, MikeAmes should not use motorcycle oil because it's formulated for use in a wet clutch. I do believe Mobile makes a 10W-40. I use Mobile 15W-50 in the summer, and 10W-30 in the winter.

 

Kawierider:

Funny topic. This came up last month here and I was told by someone that even the CVT trannies use the oil as a lubricant. I thought it sounded strange but they insisted they can't use automotive oil either.

In that case Mobile One is great but Valvoline Syntec is cheaper, and so is the Castrol Synthetic.

 

Check Out All About Oil fore more information than you probably want.

 

Obviously, whoever who said that had never pulled the CVT cover off their quad. The whole mechanism is external, with no lubricant whatsoever.

 

I use motorcycle oil in my suzuki now, but every other atv ive owned ive used auto oil in. NEVER had a problem out of any of them. 300ex I bought in 97 has ALWAYS used auto oil and ive hammered the crap ,outa it. no engine problems at all. I sold it in 02 to my cous and hes still riding it. Now this doesnt mean you wont have any probs but i never had out of 12 atvs ive owned. "w" means winter. basicaly when the oil is cool it is at 10 visc. when it heats up the compounds expand and make it more viscous or to 30-40 or whatever the # is. look at the site provided it probably tells this, maybe a little more detail. pay close attention to the filters to. dont go to the parts place and buy a fram or some cheap junk like that( same for autos, buy a purolater or wix or something). Buy the dealer one. or a GOOD after market. I worked at Mobil Blending a Packing (B&P) plant in texas for a while, and we filled honda motorcycle and auto quart oil bottles with THE SAME OIL! Yamaha motorcyle oil , toyota auto oil and some others were filled with ALL THE SAME OIL!. Mobile 10W40 10W30 and some others!. im not telling you to use auto oil but from MY experience Im not affraid to.

 

Zex129, I totally agree. Out of laziness or just being a cheapass, I used to use auto oil in my old KLR-650. I was chastised regularly by the dealer and parts people for this, but the thing ran great, and I never had a problem with the transmission or clutch. It probably wasn't the best thing for it, but after 35,000 hard miles, it still ran great.

 

So I guess just manual wet clutches are the only one.

But isnt a 300ex a manual wet clutch?

I suppose if you used the cheap auto oil without the friction modifiers it might work.

 

The 300ex was an example. Ive used it in the semi auto atvs too. You know, gears and shifter , no manual clutch. I also use auto oils in my 2 wheel machunes too. 900 ninja and 1200 zrx. and have used it in alot of different bikes/trannies. NO problems. and like i said at Mobile the oils we bottled were the exact same thing. alot of the auto and Motorcycle oile out there are Mobile oils. Mobile is what i use in my autos.( not to advertise) but to me it cant be beat. I change my oil regularly when needed, depending on miles or how hard ive ridden. And like i said be sure to use a good filter. Me and some of my old 2 wheel racing/riding buddies (streetbike), did some good comparisons on them, taking them apart and all. I can get a good link to a really detail look at filters that we circulated around our forum, TRISTATESPORTBIKES.
I used to run Castrol 20W50 in the 300ex. It is pretty hot here in south/east texas, and hard /slow forest riding really heats a bike up. But never had a prob. I run mostly 10W40 oils now in my bikes/atv. mobile in the kawis. My atv i use dealer oil mostly cause its easy to get while im getting my filter. Castrol actually make a bike oil specificall for motorcycles, but ive never used it. Mobile makes some for bikes too, but not sure if it is actually really any different from there regular oils, its been a while since i worked there.