Just rebuilt the front differential on my sportsman 500efi. Replaced everything but the gears. Added correct fluid and put it back together. 4x4 works but it wont disengage unless I put it in reverse.

I also replaced thrust plate due to severe wear, I completely removed the set screw for the thrust plate while cleaning it out.
Is there a factory setting for putting this back in with a new thrust plate? Would this be why 4x4 wont disengage without reverse?

Also noticed 4x4 is really jerky and pulls to the left hard, this is all when the atv is in the air and testing it on jack stands.

Any help is appreciated.

 

When it's on jack stands does it go into 4x4 when the switch is on 4x2?

 

No, if I start it up and have it in 2x4, the front tires don't spin, if I turn 4x4 on they do. but it wont disengage if I turn it back to 2x4 unless I put it in reverse first. Very jerky and pulling hard to the left also. Correct Polaris fluid and correct amount.