Walker 16663 Catalytic Converter with Integrated Exhaust Manifold - Rear

Walker EPA Manifold Converter 16663

Walker EPA 16663 is a direct-fit catalytic converter with integrated exhaust manifold for select Toyota, Lexus, and Toyota Sienna applications. Built with a stainless steel body and ceramic substrate, it is designed for OBDII vehicles and EPA emissions requirements.

Key Features

• Direct-fit catalytic converter with integrated exhaust manifold
• Stainless steel converter body for corrosion resistance
• Ceramic substrate material
• 6-bolt welded flange inlet and 2-bolt welded flange outlet
• Round inlet and outlet port shapes
• Pre-catalyst oxygen sensor location
• Includes inlet gasket
• Mounting hardware included
• Fits EPA Federal Emission equipped vehicles

Product Details

Walker EPA 16663 is part of the Walker Ultra EPA-Compliant Manifold Converter line, a product line focused on EPA-compliant replacement converters for import and domestic OBDII vehicles. This unit uses a stainless steel converter body, a ceramic substrate, and a direct-fit layout to match the original exhaust manifold configuration on covered applications. The overall length is 18.71 inches, with a 5-inch converter body length and a 4-inch round body profile.

This part cross-references Walker Exhaust 52545 and 52548 for the same application. It is commonly searched as a catalytic converter for Toyota Sienna, Toyota Highlander, and Lexus RX350 rear firewall-side exhaust repair, and it is identified by part number 16663.

Vehicle Fitment

• Fits 2014-2016 Toyota Highlander, Rear. Fire Wall Side; Fits Fed. & Calif. Emission Models; Not legal for sale or use in California and other CARB-compliant states. Legal in New York and Maine on EPA Federal Emission Equipped Vehicles only. Exhaust gasket is recommended; additional part(s) needed to complete installation: 31332; Ultra Type; EPA.
• Fits 2012-2016 Toyota Sienna, Rear. Fire Wall Side; Fits Fed. & Calif. Emission Models; Not legal for sale or use in California and other CARB-compliant states. Legal in New York and Maine on EPA Federal Emission Equipped Vehicles only. Exhaust gasket is recommended; additional part(s) needed to complete installation: 31332; Ultra Type; EPA.
• Fits 2012-2015 Lexus RX350, Rear. Fire Wall Side; Fits Fed. & Calif. Emission Models; Not legal for sale or use in California and other CARB-compliant states. Legal in New York and Maine on EPA Federal Emission Equipped Vehicles only. Exhaust gasket is recommended; additional part(s) needed to complete installation: 31332; Ultra Type; EPA.
• Fits 2011 Toyota Sienna, Rear. Fire Wall Side; From 09/2011; Fits Fed. & Calif. Emission Models; Not legal for sale or use in California and other CARB-compliant states. Legal in New York and Maine on EPA Federal Emission Equipped Vehicles only. Exhaust gasket is recommended; additional part(s) needed to complete installation: 31332; Ultra Type; EPA.

Common Repair Uses

• Check engine light related to catalyst efficiency or exhaust flow
• Cracked or leaking exhaust manifold assembly
• Rust damage at the manifold or flange connections
• Failed emissions inspection on EPA Federal Emission vehicles
• Exhaust noise caused by manifold or converter leakage

Installation Notes

Verify emissions compliance before ordering. This converter is not legal for sale or use in California and other CARB-compliant states. For covered applications, an exhaust gasket is recommended, and additional part 31332 is listed as needed to complete installation. Confirm the rear, firewall-side placement and the 6-bolt welded flange inlet / 2-bolt welded flange outlet configuration before installation.

Quality Assurance

Walker EPA 16663 is built for EPA-compliant replacement use on select OBDII vehicles and follows the Walker Ultra EPA-Compliant Manifold Converter product line specifications. It is designed to meet the emissions requirements stated for the listed applications.