Walker 83397 Catalytic Converter with Integrated Exhaust Manifold - Front

Walker CalCat Catalytic Converter for Nissan Altima

Walker CalCat 83397 is a catalytic converter with integrated exhaust manifold built for direct-fit replacement on select Nissan Altima front applications. It is CARB certified and validated for OBDII and non-OBD vehicles, with an OE-style fit that supports emissions compliance and proper exhaust routing.

Key Features

• Walker CalCat manifold catalytic converter, part number 83397
• CARB Executive Order D-182-63 for California and other CARB-regulated states
• Stainless steel converter body with ceramic substrate material
• 5-bolt welded flange inlet and 2-bolt welded flange outlet
• Pre-catalyst oxygen sensor location
• Includes front gasket for the listed application
• Direct-fit design for 2004-2006 Nissan Altima front exhaust service

Product Details

Walker CalCat is the Walker emissions line focused on CARB-compliant replacement converters for OBDII and non-OBD vehicles. This 83397 unit is designed as a catalytic converter with integrated exhaust manifold, using a stainless steel housing and ceramic substrate to match the OE-style layout on the Nissan Altima front position. The overall length is 19.5 inches, with a 4-inch round body and oval inlet to round outlet configuration.

Fits 2004 Nissan Altima, front. Fits 2005 Nissan Altima, front. Fits 2006 Nissan Altima, front. This part cross-references 31658 for the same application.

Common Repair Uses

• Replacing a failed front catalytic converter on a Nissan Altima
• Addressing emissions test failure related to converter efficiency
• Restoring proper exhaust manifold and converter fitment after corrosion or damage
• Correcting exhaust leaks at the flange connection points
• Meeting CARB-compliant replacement requirements in regulated states

Installation Notes

• Verify the engine family number and CARB application details before installation.
• Additional part 31658 is listed as needed to complete installation.
• Confirm the pre-catalyst oxygen sensor location and flange style match the vehicle.
• Use the included front gasket during installation.
• Check exhaust alignment and fastener condition before final tightening.

Quality Assurance

Walker CalCat converters are designed, tested, and validated to meet CARB standards for the listed applications. Part number 83397 carries CARB Executive Order D-182-63 and is approved for sale and use in California and other states that require CARB-compliant replacement converters.