Working on an older crown w/ a steering issue. The truck has an orbitrol w/ a chain attached. It that turns a drive shaft, that turns gears to the drive train. At times the orbitol is difficult to turn as if it loses hydraulic pressure in part. Steer motor is good. Orbitrol has a slight leak, didn't check pump pressure. Anyone know if these trucks have any inherant issues w/ pumps or orbitrols, (change both)? Drive train seems to be ok.