Yep, like the other fellas say, the equivalent/cross-ref to a Motorcraft FL400, Fram PH3600, Supertec 3600, etc... will work perfectly on your Kohler Command 20. I use the Carquest premium or Napa gold equiv on mine. The larger filter housing increases your oil capacity some. I had a problem with a Fram filter many years ago that I caught right out of the box. I'm with Bob on the Fram debate. I don't think basic fram oil filters are any worse than other brands in that price range. I'd only buy a basic fram if was the cheapest thing on the shelf in that particular store. I recently bought a fram oil filter for the Ecotec 2.2L 4 banger in my car. It's a Bulgarian made filter and is identical to Champion Labs brands like Supertec, etc.. my point is, all filter p/n's are not manufactured by the same company. More confusion to add to the pot!
Joel