7.3 Powerstroke Turbo Compressor Outlet O-Ring — Ford F4TZ-9E436-A

Genuine Ford F4TZ-9E436-A O-ring for the 7.3L Powerstroke turbo compressor outlet. It seals the compressor housing to the Y-pipe so boost stays in the charge-air path instead of leaking into the engine bay. When the factory seal hardens, flattens, or tears, you lose boost, hear a whistle under load, and give up power even if the turbo is still good. This is the correct direct-fit OEM replacement for that joint.

• Fits 1994–early 1999 7.3L Powerstroke (through 12/6/98), including F-250, F-350, F-450, F-550, F-Super Duty, and matching E-Series vans
• Also known as turbocharger / duct / outlet gasket; crosses to 1818372C1
• Does not fit late 1999.5–2003 7.3L engines — those use a different outlet seal
• Replace it anytime the turbo, compressor housing, or Y-pipe is off, or when a boost leak test points to the compressor outlet