my b7800 is the worst. I often start out doing a grading job since the loader is great; only to end up putting the 7800 up and getting out the old b2150 to finish the job. I ve tried everything ive read on here. grinding the stops, adjusting and more adjusting. It will either throw the box blade so high you think its going to land in front of the tractor or only move a mm or two as it goes up.