"Best guess depends on year an
"Best guess depends on year and horsepower.
1974-1991
bleed down is almost always the valve body. Sometimes water gets in system and causes rust on bypass valve. otherwise chrysler, Force, and USMarine rams last 30 years or more. Smart move is to have entire pump serviced. New seals on motor and rebuild/replace valve body. Motor lasts forever if you keep water out. Bleed down is red flag for old & leaky motor seals too.
1991-1998
check color of fluid. If red then you are a victim of mercury corner cutting. Mercury ATF (red stuff) contains additives that eat system up from inside out. The exact same rams that lasted 30 years for chrysler only last 13-15 for Mercury. Only smart choice is entire system overhaul. Otherwise you risk repeating failure. If fluid is tan then ignore above. If tan with round valve body then same as 1974-1989. If tan with square valve body (manifold) then system needs to be diagnosed and tested. Probably debris, maybe rust. But if you don't figure out why or where from then problem comes back."