AP Exhaust 774398 Catalytic Converter - Left

Brand	AP Exhaust 774398
Position	Left
Product line	5FMXT05.4R4P
Fits	Ford · 3 vehicles

OE dimensions. Built to exact OE dimensions for straightforward replacement.

Efficient substrate chemistry. Proprietary substrate loading improves converter efficiency and lowers cost.

Advanced manufacturing. Automated production and spinner welding help ensure consistent build quality.

$1,069.13Free shipping

In stock · usually ships same day before 1pm CST

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AP Exhaust Catalytic Converter for Ford F-150

AP Exhaust 774398 is a direct-fit catalytic converter for select 2004-2005 Ford F-150 applications on the left side. It is built to OE dimensions for proper fitment and is engineered for California emissions compliance on the listed vehicles.

Key Features

Direct-fit catalytic converter for the left side
Compatible with 2004 Ford F-150, left
Compatible with 2005 Ford F-150, left
California emissions application with EO Number D-798-14
Built to exact OE dimensions for fitment accuracy
AP Exhaust 774398 / 4FMXT05.4R4P product line identification

Product Details

The AP Exhaust 4FMXT05.4R4P line uses advanced substrate chemistry to support efficient catalyst loading while keeping manufacturing consistent. Automated production processes and spinner welding help maintain dimensional accuracy, which is important when replacing a catalytic converter on a Ford F-150. AP Exhaust 774398 is listed for the left-side position on 2004 and 2005 Ford F-150 models with California emissions requirements.

This part cross-references 4FMXT05.4PP7 for the same application.

Common Issues This Part Can Address

Failed emissions testing due to a worn or inefficient catalytic converter
Check engine light related to catalyst efficiency codes
Restricted exhaust flow from a deteriorated converter substrate
Replacement needs after converter damage or internal breakdown
Fitment problems when an OE-style direct-fit unit is required

Installation Notes and Tips

Verify the vehicle is a 2004 or 2005 Ford F-150 with the left-side California emissions configuration before ordering. Match the EO number and existing converter layout to confirm application. Professional installation is recommended so the exhaust connections, sensors, and sealing surfaces are checked during replacement.

Quality Assurance

AP Exhaust uses controlled manufacturing processes and OE-dimension construction to support consistent fitment and emissions compliance on the listed applications.

This part fits 3 vehicles

Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

Year	Make	Model	Drive Type	Liters	Cylinders	Position	Notes
2005	Ford	F-150	RWD	5.4L	V8	Left	Direct Fit - California; 5FMXT05.4R4P; Legal Note: In Compliance with California Emissions Requirements; EO Number : D-798-14; 5FMXT05.4R4P; 5FMXT05.4R4P
2004	Ford	F-150	RWD	5.4L	V8	Left	Direct Fit - California; 4FMXT05.4R4P; Legal Note: In Compliance with California Emissions Requirements; EO Number : D-798-14; 4FMXT05.4R4P; 4FMXT05.4R4P
2004	Ford	F-150	RWD	5.4L	V8	Left	Direct Fit - California; 4FMXT05.4PP7; Legal Note: In Compliance with California Emissions Requirements; EO Number : D-798-14; 4FMXT05.4PP7; 4FMXT05.4PP7
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