I have an old 44 inch cut 18hp craftsman garden tractor and I need to replace the belt and do not know what size I need The one that was on there was not the correct size Thank You

Go to: sears.com and click on the Parts tab, then enter your model #, then choose to look at the diagram to be sure of the part needed. Then look at the parts list to get the part #. Then you can go to a mower, or auto parts store and cross reference the # for an aftermarket, or different name brand belt.
I do not want aftermarket, or a different brand name belt on a mower. I prefer to keep each mfg.s units o.e.m. and use only o.e.m. parts.