Walker 81940 Catalytic Converter - Rear Right

CARB-Compliant Direct-Fit Converter

Walker CalCat 81940 is a direct-fit catalytic converter built for specific Nissan applications and validated to meet CARB standards. It is engineered for an OE-style fit on the rear right position, with a stainless steel body and ceramic substrate for emissions system service on select Frontier and Xterra models.

Key Features

• Direct-fit design for specific vehicle applications
• CARB certified for use in California and other CARB-regulated states
• Large oval stainless steel body with ceramic substrate
• 3-bolt welded flange inlet and 2-bolt welded flange outlet
• Pre-catalyst oxygen sensor location
• Fits the rear right position on select Nissan Frontier and Nissan Xterra models
• Walker CalCat line focuses on CARB-compliant replacement converters for OBDII and non-OBD vehicles

Detailed Description

Walker CalCat 81940 is a specific-fit catalytic converter for 1999-2004 Nissan Frontier and Nissan Xterra rear right applications. It is designed for vehicles requiring CARB Executive Order D-182-52 compliance and is listed for select engine families across those model years. The part number 81940 is built with a stainless steel body, ceramic substrate, and OE-style flange connections to match the original exhaust layout more closely.

The Walker CalCat product line is aimed at emissions repairs where CARB legality matters. For this application, the converter is legal for sale and use in California and other states that require CARB-compliant replacement converters. This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application.

What It Helps Address

• Failed catalytic converter emissions testing
• Check engine light concerns related to catalyst efficiency
• Exhaust restriction from a worn or damaged converter
• Replacement needs for CARB-regulated Nissan Frontier and Xterra exhaust systems
• Fitment issues caused by non-direct replacement parts

Installation Notes and Tips

Fits 1999-2004 Nissan Frontier, rear right. Fits 2001-2004 Nissan Xterra, rear right. Additional parts are noted in the fitment data for installation completion, so verify the full exhaust configuration before beginning service. Confirm the engine family number and CARB Executive Order details against the vehicle before installation. The inlet uses a 3-bolt welded flange and the outlet uses a 2-bolt welded flange, so matching the original flange style is important for proper alignment.

Quality Assurance

Walker CalCat converters are designed, tested, and validated for CARB compliance and OE-style fitment. Part number 81940 is built for regulated emissions service and is backed by Walker’s direct-fit converter engineering for specific Nissan applications.