I have a 4x6 homemade wooden trailer that I tow with my mower. I had attached some wheelbarrow wheels to it but they have broke and bent all summer long. I'm looking at getting a 2000# or 3500# axle to replace it. But, to order it, I need to find out what size hub face to select. I will not be using leaf springs, insted u-bolting it to a 4x4 on the frame of the trailer. Any help would be appreciated. Heres a picture of the trailer.