Fox Acoustics FoxBox® 2007+ GM Crew Cab Quad 8" Subwoofer Enclosure

FoxBox® 2007+ GM Crew Cab Quad 8" Subwoofer Enclosure is a vented, two-chamber box designed for GM crew cab pickups, built to extract deep bass from an 8" woofer behind the rear seat in a durable, Line-X finished enclosure. It fits 2007 and up GM 1500/2500/3500 crew cab trucks and, on 2019+ models, requires removal of the under-seat storage tray.

• Sub Size: 8" x 4" — designed to house an 8" woofer with a corresponding mounting footprint, ensuring proper fit in typical GM crew cab installations.
• Sub Hole Size: 7.25" — mounting cutout required for the woofer is 7.25 inches in diameter.
• Mounting Depth: 6.75" — usable space behind the mounting surface; verify your vehicle’s rear-cab clearance before installation.
• Max Magnet Diameter: 7" — woofer magnets up to 7" diameter are compatible with this enclosure’s internal clearance.
• Internal Air Volume: 1.4 ft³ × 2 — two internal chambers, each offering 1.4 cubic feet of air volume for balanced bass response from a single enclosure.
• Tuned Frequency: 36 Hz — the enclosure is tuned to 36 Hz to emphasize deep bass extension from the 8" driver.
• Finish: Black Line-X spray coating — durable, easy-to-clean exterior that stands up to rough truck environments.
• Compatibility & Installation Notes: 2007+ GM 1500/2500/3500 Crew Cab; not for extended/double cab; 2019+ models require removal of the under-seat tray; 2014–2018 models require a 5/8" rear-seat spacer kit (included). The kit includes 8 spacers placed on rear-seat bolt studs and is shipped with the box.
• Packaging & Assembly: Shipped in two pieces and screws together with a steel connector plate for final assembly.

Benefits: In GM crew cab builds, this dual-chamber, vented enclosure delivers deep bass from an 8" woofer while preserving rear-seat and cargo space. The 36 Hz tuning and 1.4 ft³ per chamber provide strong low-end presence without overloading smaller cabins. The included spacer kit for 2014–2018 models facilitates rear-seat clearance, while 2019+ models require removal of the under-seat tray. The rugged Line-X finish and a two-piece design with a connector plate simplify installation and long-term durability in a truck environment.