I would jack it up off the ground and make sure all the wheel bearings are good but gabbing each tire individually and moving side to side. I would also have someone turn the steering wheel with the tires on the ground and make sure your tie rods are not word.  Check the service records. Look underneath to see if anything is broken. Rotate all the wheels and ensure there are no torn or worn CV Joints or Boots.  With the back end jacked up, have someone hold the brake while you turn the rear wheels.  The brake will simulate a slight load and will give you an indicator if any of the bearings are going out in the rear.  Make sure to turn the wheels back and fourth hard.  I was able to see my rear diff/spool was loose and was able to see when the bearings were starting to go in the rear.

Lots to look at...those are just some suggestions. I am sure others will have many more ideas.

Cannot wait to try them

Will be going to the Red River Riding Trails in Bulcher, TX on July 3rd for the weekend.  We may consider going to Gator Run Park in Easton, TX but we do not know anyone that has been who could tell us about it.

Anyway, hope that all the parks are full but the gas bills may be keeping people at home

Thank you for the input.  One more question is....with the larger tires and wheels it is harder to steer or easier?

If the diff on you Rhino is moving up and down at all it will destroy your frame.  YES Warranty offered to replace my frame or build a brace and I opted to have the brace made.  If I had taken a new frame it would have come lose again in the future.  Obviously Yamaha had once thought about bracing this item because there is an open bolt hole on the rear case of the diff (which is right where they braced it.

All,

I took my 2005 Yamaha Rhino in for service because the rear diff was popping. Appears it is a very weak link as when under load it would literally move up and down. I fought with the YES Warranty about the issue and they finally admitted to me that the diff has insuficient bracing that can cause frame damage if not fixed. Yamaha made a brace for me under warranty and now the diff appears to be secure and no more popping sounds.  By the way, this unit is stock with stock tires and wheels and I do all my 4-wheeling in Texas.