You have unrequested lift. Common to 7400 models. You need to replace the SOL3 valve. It also can affect the maximum lift when picking up a big load, the lift is very weak. The sol is easy to replace. Its right beside the prop valve with a large lock nut. replace the SOL3 valve but do not over tighten the lock nut. You may have to adjust the Prop valve after. Do the free lift cyls bang hard when collapsing the last 2 inches....if so, the cushions are shot and there will be debris going into the manifold.