6659 Wheel Knuckle Vacuum Oil Seal Installer Axle Tools. Vacuum oil seal installation tool works on 1998-2004 Ford F-250 F-350 F-450 and F-550 4X4s having the vacuum-operated front axle. Application: 1998-2004 Ford F-250 F-350 F-450 and F-550 4X4s having the vacuum-operated front axle.