After receiving our new 2015 RZR 4 900 we found there was a noise issue with the front differential. We dropped off our new 2015 RZR 4 900 at a Polaris dealership where it sat for two weeks. After contacting then we were told that Polaris stated to them this noise is normal.
Here is a video of the unit with the noise. It sounds like marbles in the differential
After receiving the RZR back we started to research how differentials work. We also contacted several who raced ATV's and Side by Sides regarding questions on lubrication. We felt that the noise was due to the longer drive shaft. We also felt that the angle of the differential was off.
We then added 2 washers to the rear part of the differential lifting is up. We also added a thicker drive oil. Since this unit is located in AZ we went with Royal Purple Max Gear Synthetic 75W 140.
Picture of the front differential under the unit. Again we added the washers to the rear part of the front differential where it connects to the axle.
Here is a video of our outcome.
Total repair time was less than one hour. Total cost less than $15. We have now over 40 hours on this RZR4 and the sound is now completely gone. Any questions feel free to call Thor at 815-321-3888.