Hey guys. So ive got a problem with the wrx. All the symptoms point to having a loose main shaft nut on 5th gear.. pops out of 5th gear on decel. Or off throttle.. feels like shifter is being pushed out of gear on acceleration but stays in gear until i decelerate then pops into nuetral.. and doesnt like to go into reverse. And stil shifts and drives fine in every other gear.. its a 96 wrx 5 speed. Just wondering where to buy a replacement nut and if anyone has any tips on how to do it?