Originally Posted by
InspGadgt
As for the rear axle the F109 one will work fine. The F104, F103, and F109 all have axles with the same dimensions. The only difference is the F104 rear axle has the thrust bearing assembly inside the diff hub instead of inside the wheel.
Speaking of the F104 diff. I am converting my F109 diff assembly to the F104, so you do not have to tighten the diff every time that you change tires, but if you look at the instructions it looks as though you have a bearing on each side of the spur gear between the inside and outside diff housings. Now I know that does not make sense, but it shows that in the instruction on the Tamiya and 3racing's instruction manual. I have attached a pic out of the manual.
Thanks, Mike