Awful vibration under load or quick acceleration 2012 rzr 4 800

I just bought a used 2012 rzr in good shape with 800miles on it but my first day out noticed a terrible vibration when i put it in 4×4 drive after accelerating. The vibration shook the entirr machine violently and stopped when i stopped the machine and let it idle. It only happens in 4×4 or in 2×4 when you are trying to accelerate at the.bottom of a hill. The belt is brand new and installed correctly, i just cannot figure out what would cause this intermittent but violent vibration?

Any thoughts? Thanks!

Awful vibration under load or quick acceleration 2012 rzr 4 800

I just bought a used 2012 rzr in good shape with 800miles on it but my first day out noticed a terrible vibration when i put it in 4×4 drive after accelerating. The vibration shook the entirr machine violently and stopped when i stopped the machine and let it idle. It only happens in 4×4 or in 2×4 when you are trying to accelerate at the.bottom of a hill. The belt is brand new and installed correctly, i just cannot figure out what would cause this intermittent but violent vibration?

Any thoughts? Thanks!