GM Exhaust Manifold 85012559 EPA Code ACX

Catalytic Converter, Converter. Y pipe combines into single exit... 3 cats on pipe. Silverado, Sierra 2500 HD. Gas. Silverado, Sierra 3500 HD. Replaces: 87845900

General Information and Conditions

Every catalytic converter we offer is professionally recertified through an EPA-compliant process and individually tested before being approved for sale. Each unit is carefully restored and inspected to provide OEM-quality fitment, durability, and emissions performance.

Mechanical Restoration

All threaded ports, including O2 sensor bungs, are cleaned and re-tapped. Flange surfaces are precision-machined flat, and damaged studs are replaced to restore proper sealing and OEM-quality fitment.

Performance Testing & Certification

Each converter is tested on a full-scale engine dynamometer under simulated real-world driving conditions. CO, HC, and NOx emissions are measured in real time both before and after the converter to verify its efficiency and confirm that it is properly reducing harmful exhaust emissions.

Every converter must pass our dynamometer testing and quality-control standards before receiving Accurate Certified OEM approval. This makes it a reliable and cost-effective alternative to purchasing a new OEM part, not a typical untested used converter or aftermarket replacement.

Accurate Certified OEM is one of the few companies in the country authorized to operate under an EPA-issued certification code (ACX). Our converters are individually tested according to strict environmental and quality standards, providing a level of performance verification, quality, and accountability you will not typically find with aftermarket products or non-certified sellers.

California and CARB-State Notice

This catalytic converter is not CARB-approved and does not carry a California Air Resources Board Executive Order number. It is not available for sale, shipment, or installation in California or any other state or jurisdiction requiring a CARB-approved catalytic converter for this application.

Orders with shipping addresses in restricted states or jurisdictions will be canceled. Buyers are responsible for confirming compliance with all applicable state and local emissions requirements before purchasing or installing this product.

Vehicle Fitment

Shipping and Handling

• Free Ground Shipping if Ordered by 3PM

Warranty and Returns

• 1 Year Warranty