So I don't have a picture but will post one later. I have had my 06x front end apart for a couple of weeks waiting for it to warm up enough to put it back together. Replaced driver's side compression rod and drive axle and have the whole knuckle removed at the moment to replace the ball joint. Now I don't remember where this big washer came from and don't see it in the FSM. I have the front axle and front suspension chapters and don't see this big rounded diamond shaped washer in the exploded views. It's a pretty unusual washer and is big like transverse link bolt size or compression rod nut size etc. I'm hoping the description is enough for someone familiar with the front end pieces to know where it goes.

 

I got nothing

 

I guess oblong might have been a better description. After looking at the FSM again it seems like it has to go under the nut holding the tie rod end. There are no other nuts in the whole diagram. It just looks like a normal washer in the drawing rather than this oblong looking one.