The Reese Super Titan 4000 Trailer Hitch # 38208 referenced in your question is a universal-type hitch that is designed for "C" channel style frames that are approximately 34-34-1/2 inches wide. If this matches the frame on your Kenworth w900 semi-tractor, then this heavy-duty hitch will be a good option.
Otherwise, we do have a nice selection of universal, weld-on hitches available that you can look through that might be a good fit for your w900. The Draw-Tite Ultra Frame Service Body... view full answer...