Im going to refer to the inner tub as a basket and the outer tub as the tub.
Well,
The 9806 I have infact does have the "self clean" filters at the bottom like the 9800. Beekeyknee did something like this before and he just sprayed over the filters with silicone as him, like I, dont believe they do anything.
While dimensionally they may look like it will fit, again, it wont. On the 9800 the balance ring at the top of the basket is curved and is designed to act as a clothes guard to prevent items from going in to the outer tub. The metal tub cover is supposed to have close clearance with the basket, more or less like a seal to block clothes. The tub on the 9800 is also lightly flared at the edge so the tub cover clamp and rubber seal have a place to sit and mate to.
ON the 9806, the tub flare is more pronounced and if I remember correctly has detents in it to allow the plastic clamps to slip in and lock on the tub. Furthermore, the basket, as I said before, has a precast balance ring that is stamped in to the basket. The precast ring is cast in a plastic mold, and this plastic makes up part of the clothes guard for the 9806 machines. This is the key difference, you need the 9800 basket, tub, and tub cover to make a proper seal to prevent the clothes from going over in to the tub, and same thing with the 9806, none of these are interchangeable. They're not interchangeable as the tub flare, the clearances between the balance ring and covers etc wont match if you try to interchange.
Lastly, if you did decide to swap the tub, tub cover, and basket from the 9800 chassis in to the 9806, it still wont fit right as the lid opening hole is much larger on the 9806, it is not a perfect circle like on the 9800, its more of a D shape.
Personally I love the 9806 and I think it is a fantastic washer, Id leave it the same and keep both the 9800 and 9806 as is. I also believe the 9800 has the orbital drive, do you have a long stroke transmission?
[this post was last edited: 11/5/2018-04:47]