The wheels are print in place with an additional fixing piece to make them more secure. 

I had seen a similar print in place design but i didn't like the fixing method and now i couldn't find the original author
 

My Elettrolux dishwasher has a pin with a diameter of 5.4 mm and a length of approximately 14 mm, the wheels are 40 mm in diameter and the prints has rather tight tolerances to have as little play as possible, after printing it may be necessary to give light hammer blows to free the wheel. 

I printed them with my X1 Carbon with PP-CF filament (originally made of PP) for chemical and temperature resistance and the carbon reinforcement allows resistance to wear. I've been using them for a month and the material has no problems.

Do not use filaments with low temperature resistance, PETG does not last more than 5 cycles, it expands and deform its shape. I haven't tried abs or nylon.

if there are problems with the prints or different sizes, please give me some feddback to improve design