the model number on the frame says 1693840... i also have an update. i replaced the drive belt, it was really worn, and had oil on it. (need to find and fix the leak). i tried it out on that same 45 degree incline... went about halfway up that time...improvement, but not finished. i dumped the hydraulic oil i used a week ago, got some STENS 20W-50 hydro fluid. filled it up and tried again...this time, it went up over the hump and actually spun the tires at the top.my better half tells me it is much quieter, not the loud whining noise like before. all i know is, it is better than it was. still tossing the idea of tearin it down to check the pump for wear, as well as that filter that is buried under pump housing. if someone used it on a mostly 'flat' yard...it would be fine i believe.!! any thoughts?