3-Inch Cat-Back Exhaust System

The Thermal R&D 3" Cat-Back Exhaust System (B917-C917) is engineered to elevate the performance and sound of your 2020-2027 Ford Explorer ST. This full 3-inch front pipe back system is constructed from T304 mandrel-bent stainless steel for durability and corrosion resistance. A key feature of this exhaust system is Thermal R&D's True Helmholtz Technology. This proprietary design targets and neutralizes low-frequency exhaust tones that can cause cabin drone, resulting in a sound profile that is deep and aggressive under throttle, yet refined and comfortable during cruising. The system includes brushed finish rear Helmholtz Chambers and 4" dual angle cut polished tips that fit the OEM valance without the need for cutting or welding. Installation is straightforward, utilizing factory hanger locations and mounting to OEM catalytic converters and downpipes. The system is backed by a limited lifetime manufacturer's warranty. **Important Compatibility Note for 2026+ Models:** Some 2026 and newer Ford Explorer ST models may be equipped with a Gasoline Particulate Filter (GPF), depending on trim and market. Installation on a GPF-equipped vehicle may trigger a Check Engine Light, rendering this system incompatible. To check for a GPF, consult your VIN or the Vehicle Emissions Control sticker under the hood. If GPF is listed, this exhaust will not fit. Contact customer support for assistance in confirming compatibility or for information on developing GPF-compatible systems.