I have an 84 which is last year before TII's. Only difference between an 84 and newer is TII has larger tailings elevator and 6" longer sieve to acommodate the corner openings for returns..and worst of all, they speeded up the shaking action on the sieves. This change has a nasty habit of destroying the whole shoe. Older than 85 was normal and long lasting. Get an 83 or 4. Both have two speed planetary cyl. drive, tighten clean grain elevator from the ground, and I can't think of rest. Great machines. GS