I just bought a 05 rubicon and I'm looking for engine oil recommendations. The dealer told me to use honda synthetic but the book says not to ,so I called honda and they tell me to only use the honda GN4 oil only. Love this machine and I want to take the best care of it that I can. Please help

 

You're going top get a lot of different answers.

For the first 3000 miles I used Valvoline AllClimate 10w40 oil. I then switched to Valvoline 10w40 ATV Oil. I change the oil and filter every 500 miles. I use only Honda oil filters. For me thats only 3 oil changes a year, not a big deal.

With over 5000 miles on our Rubicon the engine and trans have been 100% trouble free. I adjust the valves every 1000 miles and change the differential fluid (pure synthetic) and anti-freeze every other year. I also clean and service the air filter when ever it gets dirty. On the average about every 250 miles.

Up to this point I see no problems getting 10,000 miles out of this ATV.

 

i use the honda gn oil also.
it might be expensive but i think its worth it.
i tryed castroll 10w 40 and it seemed to make it nosier so i went beck to the honda oil.

 

If you read your owners manual for your 05 Rubicon, it says that Honda HP4 synthetic blend (without moly) is also a recommended oil, so as usual the dealership doesn't know what's going on.

After extensive study on the subject of oils, I have become a huge proponent of ESTER SYNTHETIC oils! Here you can read my opinions on GN4 and Honda oils in general--- http://forums.atvconnection.com/mess...did/457258.cfm

 

At this time guess I'll go with the valvoline atv oil. Looks like it easy to find and others are happy with ite performance.
Thanks for the input.