hey my 300 fourtrax 4x4 has problem the back tires wont spin but the front do., Whats wrong with it?

 

Humm,could be a broke stripped drive shaft,broke output shaft, bad ring & pinion or stripped axle splines.Pull the boot back at the rear of the engine at the swing arm back far enough you can see it,jack it up and see if the yoke is spinning or if the output shaft coming out the engine is snapped,another thing a little more simple is jack it up off all 4's,remove the 17mm fill plug on the differential,start it up,put it in gear and see if the ring gear is turning,if it is it is very possible you have a stripped splines on the axle.Use care & block it up well

 

well the back tires they just drag

 

Sounds like the ring and pinion,if lucky a bad bearing