Catalytic Converter for Mercury Grand Marquis (1996-2002) 4.6L Left & Right

Direct-Fit Replacement Left & Right Catalytic Converter Set for 1996-2002 Mercury Grand Marquis (Panther Platform)

What it Does: The catalytic converter set replaces deteriorated factory manifolds and mid-pipe emissions units on the 1996-2002 Grand Marquis to clear P0420/P0430 codes and restore balanced exhaust backpressure.

The Stock Mercury Grand Marquis Catalyst Washout & Frangible Substrate

Over extended heat cycles on the high-mileage Modular 4.6L 2V V8, original factory catalytic converters suffer from washcoat depletion, thermal fracture, and substrate sintering. The aging ceramic honeycomb degrades from continuous thermal expansion, causing internal matrix collapse, excessive exhaust backpressure, restricted scavenge velocity, and downstream oxygen sensor catalyst efficiency trouble codes (P0420/P0430).

The Engineering Solution

This left and right direct-replacement assembly is constructed from heavy-gauge stainless steel tubing with integrated, high-porosity ceramic substrates. Optimized washcoat loading with high precious metal distribution provides rapid light-off and effective hydrocarbon, carbon monoxide, and NOx reduction without restricting exhaust gas velocity. Robotically welded OE-style flanges match the stock Panther Platform exhaust manifold drop-downs and factory intermediate pipes, eliminating custom fabrication while incorporating precision-machined O2 sensor bungs in stock locations for uncompromised sensor response.

Technical Specifications

Compatibility

• 1996-2002 Mercury Grand Marquis GS 4.6L V8 (Modular 2V)
• 1996-2002 Mercury Grand Marquis LS 4.6L V8 (Modular 2V)
• Note: Fits models with O2 sensor ports on each side of the front converter assembly. 46-state legal (Cannot ship to CA, NY, CO, or ME).

Frequently Asked Questions

Does this fit the Panther Platform Grand Marquis?

Yes, this is a direct fit for the 1996-2002 Mercury Grand Marquis equipped with the Modular 4.6L 2V engine.

Will installing this catalytic converter set resolve catalytic efficiency trouble codes?

Yes, replacing depleted converters with these high-efficiency ceramic substrate units restores proper emissions reduction and clears diagnostic codes P0420 and P0430, provided upstream air-fuel delivery and O2 sensors function within factory specifications.

The Mercury Heavy-Duty Fleet Standard

Engineered for the demands of full-size body-on-frame platforms, this exhaust system ensures OE-grade acoustic dampening, corrosion resistance, and sustained low-RPM exhaust scavenging across hundreds of thousands of highway miles.