I have a 2006 polaris ranger 4x4 700 efi 4 wheel drive quit working we complete rebuilt the front end new bushings ,a arm ,ball joints ,took front gear box out took in to shop had it checked out came back said it worked great but when all was put back together and hooked back up 4 wheel drive still only works part time we have checked fuse it is good also tried by passing awd switch as was told by polaris and still same problem don't know what else to try so any help or suggestions would be great .........Thanks