I use them to move the digger off the tractor they are great for that. The base and casters are quite heavy. My biggest concern is the bearings that support the top plate. They are not that big and are only held by the top plate. If the plate mounting bolt is loose, expect bearings all over the floor (which explains some of the reviews complaining about it). I'm pretty happy moving 2000lbs with them, at 13200lbs I'm not sure. But good performance for the price.