If anyone can help I would appreciatte it. I have a 1970 M51A2 and it was dumping fine until the last large load. Now when I try to dump it, it just leaks fluid. I looked under the truck and it appears to be coming from the control valve. There are six bolts that hold up the valve on the passenger side frame rail. It looks like there is a gasket or o-ring that may have let go. Has anyone experienced this and if so, is there an o-ring there? Thanks !!