Normal operation for the rear differential. I don't think there is a atv out on the market that has a limited slip rear differential.

Get some better harnesses from Ruthless motorsports. Simpson 5 points are the way to go or a 4 point. I would never trust a stock belt after rolling my old Rhino again. That is impressive mileage too, any oil burning? Watch the oil constantly and always check it warm, the 660's are known to suddenly run dry...from experience.

I had one on my 660. I used a 3-5 psi from pepboys but went back to stock due to the noise. I would go to a better vacuum style pump than to a electric. Badley upgraded his to before he sold it, he may remember the brand.

:?: Moab will be off limits and we willbe going to the local gravel pit instead....damn tree huggers!

I need new tires on mine. I was thinking these would look good tucked under it.
http://www.intercotire.com/photos/a48f3ewr8ib96l_lg.jpg

A rhino 450 will do everything you want except the dunes. Top speed in stock form is 33 mph and is very noisy at about 25 mph. They will do everything of a 660 or 700 except go fast. With all accesories I still wouldn't exceed 6k for it. I sold my 06' 660 rebuilt solid with extended cage, fully accesorized with plow for 7500.00. The other drawback is a 450 is going to be hard to sell down the road too.

If you are sold on a rhino I would look at the 700. I feel the 660 design for a rhino and some things Yamaha did was not up to par. The 450 hasn't had nearly the issues of the 660 except low top speed, no display on most models, and the typical noise issue as all rhino's have. Any of them will plow snow better than your neighbors atv will, I proved it time and time again with up to 18" snowfall a few years ago.

I have nothing bad to say about the Rhino other than the noise. Here is proof of what a 450 will do, this is my mothers rhino 450 pulling around 17,500 lbs.
[youtube]http://www.youtube.com/watch?v=mcsw8x-V2Yg[/youtube]

After only getting 1800 miles out of my rhino before blowing smoke made me decide a 8% investment was worth security for 9 times the standard warranty. In five years I could easily have 4000 miles on this machine and who knows what issues on a early 2010 model.