Catalytic Converter for Hyundai Sonata (2015-2018) 2.4L Rear

Direct-Fit Rear Catalytic Converter for 2015-2018 Hyundai Sonata (LF)

What it Does: The rear catalytic converter replaces the degraded secondary emissions assembly and flex pipe on the 2015-2018 Sonata to resolve P0420 catalyst efficiency codes, seal exhaust leaks, and restore proper exhaust scavenging.

The Stock Hyundai Sonata Substrate Breakdown & Flex Pipe Shear

Under continuous heat cycles and road vibration, the factory catalytic converter on the LF chassis Sonata experiences thermal washcoat depletion. This loss of precious metal loading triggers recurring P0420/P0430 diagnostic trouble codes and causes rotten-egg sulfur odors. Concurrently, engine rocking under load places cyclic fatigue on the factory integrated flex section, inducing structural bellows cracks, exhaust gas leaks, and false upstream oxygen sensor readings that handicap fuel trim accuracy.

The Engineering Solution

Constructed with a heavy-gauge stainless steel outer shell and a durable ceramic honeycomb substrate, this direct-fit rear converter provides the cell density required for thorough HC/CO oxidation while maintaining unchoked exhaust throughput. Precision-welded 2-bolt inlet and outlet flanges mirror the OEM exhaust geometry, mating directly to the downpipe and mid-pipe without cutting or welding. Engineered as a direct mechanical replacement for OEM part numbers 28600C2400, 28600C2560, and 54965, it restores proper backpressure balance on the Theta II platform.

What's Included

• 1x Direct-Fit Rear Catalytic Converter with Integrated Flex Pipe
• Exhaust Flange Gaskets
• Mounting Bolts and Hardware

Technical Specifications

Compatibility

• 2015-2018 Hyundai Sonata 2.4L L4 Gas (SE, Sport, Limited)
• Position: Rear Underfloor (Flex-Pipe Converter Assembly)
• EPA 48-State Legal (Restricted: Not legal for sale or shipment to CA, CO, NY, ME)

Frequently Asked Questions & Fitment Warnings

Does this fit the LF Sonata?

Yes, this is a direct fit for the 2015-2018 Hyundai Sonata equipped with the 2.4L Theta II G4KJ engine. Excludes 2.0L Turbo models and Sonata Hybrid or Plug-in Hybrid variants.

Do I need to weld this unit to complete installation?

No, this assembly is engineered with factory-pattern 2-bolt flanges for a completely bolt-on replacement using standard hand tools and the supplied hardware.

The Hyundai Commuter Standard

Preserve factory cabin quietness and emissions compliance in your LF Sonata with a bolt-on assembly engineered to clear check engine lights and survive daily thermal cycling.