Is it really necessary to use the Honda GN4 oil in my machine?? It sells for about $3.00 a quart around here. I can find four stroke motor oil at Fleet Farm for $1.50.

 

JoeKrz,

I think you'll hear both sides on this one. I was really wondering about this because my Rubicon use almost 6 quarts of oil. It adds up at $3 a pop. Especially now, with winter coming on, I want to switch to synthetic to help cold starts, Hondas synthetic goes for $6 (!!!!) a quart around here. It's a ripoff, there's no other word for it. My owners manual says to use 10w-40 oil that meets a certain spec, I can't remember off hand what it is, but I know Penzoil meets this spec. I've used both Honda GN4 and Penzoil, this winter I'm going to go with a quality synthetic like Mobil 1 or Amsoil. Your Rancher takes what, 2-2.5 quarts? In your case its a couple bucks either way. I'd say use what you want. We have a couple 15 year old honda three wheelers that run great, I don't know how often (if at all) the oil was changed before we got them, and they don't even have oil filters.

 

The manual for the Honda 4-wheelers says to use GN4 honda oil that meets API specifications for SF or SG. These are basically just ratings that tell you that they meet certian standards. From what I've read, the SF or SG is old standards. SH is a newer rating, but the latest is SJ. and according to all oil companies, the SJ standard can be used in place of any of the other ones that came before it. In other words, all the standards are suppose to be 100% compatible with any previous standard.
here is a link that I've read that i think best describes all of this http://www.yft.org/tex_vfr/tech/oil.htm

 

You do not need to buy "honda" oil, but it is a must that you buy a oil made for use in a wet clutch/tranny system as it needs to have zink in it to protect the gears. Normal Auto oil has no zink and cannot protect gear or rocker arms with there high pressure nature of high revving ATV and motercycle engines. zink protects parts that have major pressure on them. When the oil is squeezed out from between gear or camshaft parts there is nothing left to protect them unless the oil your useing has zink that is a last resort backup. All motercycle (bell ray, Maxuma, AMSOIL motercycle, Yamalube, Honda, Mobile 1 motercycle) oil has zink and most heavy duty diesel oil such as delo 15W40 also does. read the Amsoil motercycle oil page about zink.

 

no way do need to spend $3/quart for gn4. I use castrol GTX oil in my 400ex and it runs fine.

 

JoeKrz, When I bought my 00' GSX-R750 I studied up on this subject well. The reason you should run a motorcycle specific oil and not general "car" oil is because of those SF, SG, SH, SJ..... ratings. SH and SJ rated oils are aimed at making newer cars run cleaner for emissions, they have much less zinc in them and more "anti-friction" modifiers in them which is good for a car which has a seperate transmission (and it's own fluid). When you use SH and SJ oils in a four stroke motorcycle engine which shares the same oil with the transmission the added "anti-friction" modifiers in SH and SJ oils actually bind with the clutch plates and causes slippage, sometimes minor, sometimes ALOT! it's just much more noticeable in a 135 horsepower streetbike. I've met a lot of bummed out guys with R1'S, GSX-R1000'S, and CBR929'S who've been running automotive synthetics and get beat by guys like me on 750's who run motorcycle specific synthetics because their clutches are slipping just enough! It does make a difference. But you'll hear many arguments on this subject! good luck.

 

I don't believe 10w-40 auto oil has friction modifiers. I have used BP/Amoco 10w40 in my Hondas for years now. I even add 25% synthetic Mobil one to the batch and have never had a problem. If you change you oil regular like I do your engine will still look almost new inside even after 350 hours and with no clutch slippage. Chet

 

RAPTORYFM660r, when I wrote my original response i felt like i was wasting too much space so i didn't explain all the facts, but you're right, automotive oils 10w40 and above (15w50, 30,40,50 straight rate included) don't have to meet the new federal specs for the new automotive emission laws. only 0w30, 5w30, and 10w30 have to. If you've noticed, their isn't a new passenger car out there that doesn't spec 5w30. thats because the manufacturers can get better gas mileage out of their new cars to just get under the new leaner fed laws even if it means a little less protection for the consumer. All that said I still stick with a "motorcycle" specific grade of oil to stay away from the new SH and SJ ratings that most oil manufacturers show on all their (10w40 and above) auto oils. Most motorcycle specific oils still read SF or SG rating. If no one believes me just go to the auto store and pick up a bottle of 10w40 Mobil 1 auto oil in the silver bottle and Mobil 1 10w40 motorcycle oil in the dark grey bottle and read the SAE rating labels on the back. Auto-SJ, Motorcycle-SG. It's a bummer Mobil charges twice the price for the "motorcycle" oil since it's supposedly "older technology".

 

This may sound completley stupid, but you can actually tell what oil's have Zink by simply flicking the bottle with your finger, it it has a metallic ping it has zink. Just tap a bottle of diesel grade oil to see.