ointlaugh First of all, I ran service trucks my entire career. Second, Dayton wheels have various sizes of spacers and wedges for the sole purpose of accommodating different width rims. The guy who "punches the clock" needs to know all the differences to do his job properly, therefore is intimately familiar with the different set-ups. As far as "change rim sizes out of the 2.5 inch for the tubeless"(whatever that's supposed to mean)- first and foremost, ALL the .5 sizes(14.5,16.5,17.5,19.5,22.5,24.5) ARE TUBELESS!! The .5 denotes a 15 degree bead taper, as opposed to the 5 degree of the whole number sizes.Second, 20" & 22.5 are completely interchangeable on the same set of spokes, as are 22" and 24.5. Maybe this is what you were trying to say, but you lack either the knowledge to say it or the ability to put your thoughts into legible sentences. Either way, it's kinda tough for someone, even one in the know,to actually understand and differentiate what you posted. So, in summary, the tire guy is supposed to know a whole hell of a lot more than just how to mount and inflate a tire. "Just puts tires on"!! And a mechanic "just turns wrenches", I suppose, while the truck owner actually has all the knowledge. Some people never cease to astonish me with their vast intelligence. Have a wonderful day, and please feel free to further educate me on the subject of truck tires and wheels, since you OBVIOUSLY wrote the book. Oh, and for the record, way back in 1997, I took a test to become a Certified Commercial Tire Service Technician given by the then International Tire & Rubber Assn.(now Tire Industry Assn). It was a 100 question timed test, and I scored 96 out of 100 in less than 30 minutes, thereby earning my certification.I'd love to see your score on the same test. I'm on here pretty much every day, so please educate me, as in your reference to a 9.00-20 being the same as a low profile 22.5.:Banghead:stirthepot