Chevrolet Silverado GMC Sierra Extended Cab (Double Cab) 1999 - 2006 (Quad 8")

Fits: 1999-2006 Extended Cab & 2007 "Classic" Body Style

Four Times the Punch. Serious Low-End Rumble.

Transform the audio experience in your classic GMT800 truck with a setup designed to turn heads. This isn't your standard dual-sub box. This custom-engineered enclosure houses four 8-inch subwoofers in a high-output ported design, fitting perfectly under the rear seat of 1999–2006 Chevy Silverado and GMC Sierra Extended Cab trucks.

This configuration is the ultimate " sleeper" setup. By utilizing four smaller drivers, you get massive cone area (comparable to larger subs) for deep bass, combined with the tight, fast transient response that 8-inch drivers are known for. The tuned port maximizes efficiency, delivering tremendous output that you can feel in your chest.

Why Choose This Quad 8" Ported Box?

• Massive Output Potential: The ported (vented) design is tuned to boost low-frequency output, making this significantly louder than standard sealed under-seat boxes.

• The "Quad" Advantage: Four 8" subs provide incredible punch and speed. It’s a unique setup that delivers surprising depth and volume from a low-profile package.

• Precision Under-Seat Fit: Engineered specifically for the 99-06 Extended Cab floor pan. The enclosure contours to the floor, allowing the rear bench seat to fold down completely into its seated position.

• Built Tough: Constructed with high-quality MDF for structural rigidity and covered in durable, OEM-match automotive carpet that blends seamlessly into your truck's interior.

Technical Specifications

Important Fitment Verification:

1. Cab Style: This box fits the Extended Cab trucks of this generation. These trucks have rear doors that open backward (suicide style) and do not have exterior door handles. This will NOT fit Crew Cabs (4 full forward-opening doors).

2. Year Range: Fits 1999-2006 models, and the 2007 "Classic" body style.