1999-2006 Chevrolet / GMC Silverado 1500 / Sierra 1500 Subwoofer Box Fitment

1999-2006 Chevrolet / GMC Silverado 1500 / Sierra 1500 GMT800 (also sold as the 2007 Classic) — subwoofer box fitment

What we researched for this specific generation: where an enclosure actually fits, what the factory speakers are, how the factory audio is wired, and which real builds and commercial products exist for it. Confidence badges say how well each figure is sourced — this is research, not manufacturer spec.

Body styles covered: Regular Cab, Extended Cab, Crew Cab

Where a box actually fits

These are researched envelopes, not a guarantee. Measure your own vehicle — the numbers here tell you what to expect, not what you have.

Crew Cab Solid

Location	behind rear seat, Non-HD Crew Cab
Outer bounding box	No independently measured raw cavity envelope found — the real Skar Audio dual-10" sealed enclosure is the best available reference point. Vehicle-specific enclosure catalogues; published box footprints are lower bounds on the cavity, not the cavity: NET Audio '2001-2006 Chevy Silverado Crew Cab Sub Box NonHD Sealed': 54 x 7 x 13 in (as printed; axes not labelled), 1.5 ft3, behind seat, full width [only 2001-2006]; NET Audio '2001-2006 Chevy Silverado Crew Cab Sub Box NonHD Sealed Jumbo': 58 x 11 x 25 in (as printed; axes not labelled), 3.25 ft3, behind seat [only 2001-2006]. Vehicle-specific enclosure catalogues; published box footprints are lower bounds on the cavity, not the cavity: Ground Shaker 'BLACK 8" DUAL SEALED SUB BOX, FITS 01-07 CHEVY SILVERADO CREW CAB': Height 14 1/4", Length 48 1/4", Top Depth 2 1/8", Bottom Depth 7 1/2" (labelled by Ground Shaker), 1.27 FT^3 total; 0.64 FT^3 per subwoofer, FITS BEHIND REAR SEAT [only 2001-2006]; Ground Shaker 'BLACK 10" SINGLE SEALED SUB BOX, FITS 01-17 CHEVY SILVERADO CREW-CAB': Height 6 1/2", Length 30 1/2", Depth 12 1/2" (labelled by Ground Shaker), 0.68 FT^3, FITS UNDER REAR SEAT [only 2001-2006].
Known obstructions	None specifically documented.

Starting points

Suggested configurations for this vehicle, not prescriptions. Run the numbers in the Box Builder before you buy anything.

Budget

Subwoofers	1x10" downfire, amp space (named product: Subthump)
Box type	downfire
Location	behind rear seat, Extended Cab

Enthusiast

Subwoofers	2x10" or 2x12" sealed (named products: Skar Audio, Non-HD Crew Cab or Extended Cab specific)
Box type	sealed
Location	behind rear seat

Door speaker fitment

Sizes and depths below are what research turned up for this generation. Confirm against your own vehicle before cutting or ordering — trim levels vary.

Front doors Likely

Factory speaker size	6-1/2" — specific confirmation for 02-04 Extended Cab trims, cross-confirmed via a dedicated forum thread and a specific 2004 model-year source.
Known obstructions	None specifically documented
Adapter bracket needed	unconfirmed
Tweeter	A-pillar — confirmed, matching the same convention already found on this era's GM full-size SUVs (Tahoe/Yukon GMT800) on other vehicles covered here.

Rear doors Likely

Factory speaker size	SPECIFIC, GENUINELY DIFFERENT FORMAT from the newer GMT900 (2007-2013) page's rear speakers: 4x6" OVAL speakers, not round — confirmed for Extended Cab trims. A distinct factory speaker shape — not the round-speaker convention used on newer GM trucks. Additional confirmation: Regular/Standard Cab trims mount a matching pair of 4x6" speakers in the REAR PILLARS instead of doors (no rear doors on that body style).
Known obstructions	Oval 4x6" format may require different aftermarket replacement sourcing than round speakers.
Adapter bracket needed	unconfirmed
Tweeter	n/a — tweeter is front A-pillar only

Factory audio integration

Factory amp / premium audio	Badge-specific finding within this generation. GMC Sierra Denali (introduced as a trim in late 2001, effectively a 2002 model within this page's span) came with Bose audio as STANDARD equipment — a genuine trim-level guarantee, not just an available option. Chevrolet-badge trim gating for the same era not independently confirmed — this finding is solid for Sierra Denali specifically, not proven to extend to a Silverado equivalent trim within 1999-2006.
Adding subs without a head-unit swap	Confirmed straightforward — multiple commercial direct-fit products exist for this exact generation.
Head unit	No replacement needed

Known integration products

Skar Audio dual-12" sealed enclosure (1999-2006 Extended Cab-specific)
Skar Audio dual-10" sealed enclosure (2001-2006 Non-HD Crew Cab-specific)
Subthump dual-10" downfire, amp space (1999-2006 Extended Cab-specific)

Mounting locations

Extended Cab Solid

behind rear seat

Multiple, named commercial products confirmed for this exact generation: Skar Audio sells a dual-12" sealed enclosure specifically for 1999-2006 Extended Cab trucks; Subthump sells a dual-10" downfire box with amp space, 6.5" mounting depth, also 1999-2006 Extended Cab-specific. The 2007 Silverado / Sierra Classic is this body, sold alongside the 2007 redesign: Sound Off titles its boxes "99-06 (2007 Classic)" and Zenclosures' 2007-2013 under-seat box "excludes 2007 Classic", so a 2007 Classic belongs with this page, not the 2007-2013 one.

Crew Cab Solid

behind rear seat

Specific, NON-HD-vs-HD PRODUCT SPLIT confirmed within this same generation: Skar Audio's dual-10" sealed enclosure is explicitly scoped to '2001-2006 Non-HD' Crew Cab trucks, while a completely separate product line (Supercrewsound's '01ChevyhdCC' series) covers HD (2500/3500) Crew Cab trucks in 8", 10", or 12" single/dual configurations — confirmed evidence that 1500 (light-duty) and HD trucks of this era needed genuinely different products even within the same body style.

Builds and products found for this vehicle

Outside links. Some are commercial products, some are owner builds posted on forums — the label says which. We do not endorse any of them.

Skar Audio (2 x 12", sealed) off-the-shelf
Custom-fit dual 12" sealed enclosure, explicitly scoped to 1999-2006 Extended Cab trucks.
Skar Audio (2 x 10", sealed) off-the-shelf
Dual 10" sealed enclosure, explicitly scoped to 2001-2006 Non-HD (1500) Crew Cab trucks specifically — a confirmed distinction from the separate HD Crew Cab product line.
Amazon (2 x 10", downfire) off-the-shelf
Dual 10" downfire with amp space, 6.5" mounting depth, Extended Cab-specific.
silveradosierra.com forum forum-sourced
Detailed forum confirmation of the 6.5" front / 4x6" oval rear factory speaker sizes.
NET Audio (sealed) off-the-shelf
1999-2006 Chevy Silverado Extended Cab Sub Box Double Sealed. NET Audio states fit years 1999-2006 (Extended Cab). Published outside dimensions: 50.5 x 15 x 10 in (as printed; NET Audio does not label the axes). Published volume: 2 ft3. Mounting depth 6.5 in. Type: sealed. Location: under rear seat.
NET Audio (sealed) off-the-shelf
1999-2006 Chevy Silverado Extended Cab Sub Box Single Sealed. NET Audio states fit years 1999-2006 (Extended Cab). Published outside dimensions: 25.25 x 15 x 10 in (as printed; NET Audio does not label the axes). Published volume: 1 ft3. Mounting depth 6.5 in. Type: sealed. Location: under the driver side rear seat.

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NET Audio (sealed) off-the-shelf
1999-2006 Chevy Silverado Standard Cab Sub Box Dual Deep Sealed. NET Audio states fit years 1999-2006 (Standard Cab). Published outside dimensions: 56 x 8 x 13.5 in (as printed; NET Audio does not label the axes). Published volume: 2 ft3. Mounting depth 5.75 in. Type: sealed. Location: behind seat.
NET Audio (sealed) off-the-shelf
1999-2006 Chevy Silverado Standard Cab Sub Box Dual Shallow Sealed. NET Audio states fit years 1999-2006 (Standard Cab). Published outside dimensions: 56 x 6.5 x 13.5 in (as printed; NET Audio does not label the axes). Published volume: 1.5 ft3. Mounting depth 4.25 (5.75 with metal back plates) in. Type: sealed. Location: behind seat.
NET Audio (sealed) off-the-shelf
2001-2006 Chevy Silverado Crew Cab Sub Box NonHD Sealed. NET Audio states fit years 2001-2006 (Crew Cab (non-HD)). Of the 1999-2006 model years here, it covers 2001-2006 only. Published outside dimensions: 54 x 7 x 13 in (as printed; NET Audio does not label the axes). Published volume: 1.5 ft3. Mounting depth 4.5 in. Type: sealed. Location: behind seat, full width.
NET Audio (sealed) off-the-shelf
2001-2006 Chevy Silverado Crew Cab Sub Box NonHD Sealed Jumbo. NET Audio states fit years 2001-2006 (Crew Cab (non-HD)). Of the 1999-2006 model years here, it covers 2001-2006 only. Published outside dimensions: 58 x 11 x 25 in (as printed; NET Audio does not label the axes). Published volume: 3.25 ft3. Mounting depth 6.75 (7.5 with metal backplate) in. Type: sealed. Location: behind seat.
NET Audio (sealed) off-the-shelf
2001-2006 Chevy Silverado Crew Cab NonHD Dual w/vents Sealed. NET Audio states fit years 2001-2006 (Crew Cab (non-HD)). Of the 1999-2006 model years here, it covers 2001-2006 only. Published outside dimensions: 59 x 7 x 16 in (as printed; NET Audio does not label the axes). Published volume: 1.09 ft3. Mounting depth 4.5 (5.25 with bump) in. Type: sealed. Location: behind seat, full width, around the air vents.
NET Audio (sealed) off-the-shelf
2001-2006 Chevy Silverado Crew Cab Sub Box HD Sealed. NET Audio states fit years 2001-2006 (Crew Cab HD). Of the 1999-2006 model years here, it covers 2001-2006 only. Published outside dimensions: 49 x 7 x 10.25 in (as printed; NET Audio does not label the axes). Published volume: 1.26 ft3. Mounting depth 5 (5.75 with metal plates) in. Type: sealed. Location: behind rear seat.
Sound Off Audio (sealed) off-the-shelf
2003-2006 Chevy Silverado 1/2 Ton Console Sub Enclosure. Sound Off Audio states fit years 2003-2006 (Silverado and Sierra 1/2 ton, Crew, Standard and Extended cabs). No outside dimensions on the product page. Published air space: 0.6 ft3. Mounting depth 5-3/4 in. Type: sealed. Location: center console. Maker: "Might fit the HD series 2500 and 3500 if the seat style is the same."
Ground Shaker (ported) off-the-shelf
BLACK 8" DUAL PORTED SUB BOX, FITS 99-06 & 07 CLASSIC CHEVY SILVERADO EXT-CAB (SKU GS-NCHVP28B). Ground Shaker states fit years 99-06 & 07 CLASSIC for Chevy Silverado Ext-Cab. Published outside dimensions: Height 8 1/4", Length 54 1/4", Depth 13 1/2" (labelled by Ground Shaker). Published volume: 1.62 FT^3 total; 0.81 FT^3 per subwoofer. Mounting depth 6 3/4". Type: ported. Location: FITS UNDER REAR SEAT; UPWARD FIRING. Maker notes: 2007 FITS ONLY OLD BODY STYLE; WILL NOT FIT TRUCKS WITH V SHAPE HUMP (USE JCHV MODELS FOR V SHAPE HUMP). The same outside dimensions, volume and mounting depth are printed for these related listings: 10" dual [GS-NCHVP210B]; 8" dual [GS-NCHVPK28B] (SoloBaric variant); 12" dual [GS-NCHVPK212B]; 12" dual [GS-NGMP212B]; 12" dual [GS-NCHVP212B]; 8" dual [GS-NGMP28B]; 8" dual [GS-NGMPK28B] (SoloBaric variant); 12" dual [GS-NGMPK212B] (SoloBaric variant); 10" dual [GS-NGMP210B]; 10" dual [GS-NGMPK210B] (SoloBaric variant).
Ground Shaker (sealed) off-the-shelf
BLACK 8" DUAL SEALED SUB BOX, FITS 01-07 CHEVY SILVERADO CREW CAB (SKU GS-WCHV28B). Ground Shaker states fit years 01-07 for Chevy Silverado Crew Cab. Of the 1999-2006 model years here, it covers 2001-2006 only. Published outside dimensions: Height 14 1/4", Length 48 1/4", Top Depth 2 1/8", Bottom Depth 7 1/2" (labelled by Ground Shaker). Published volume: 1.27 FT^3 total; 0.64 FT^3 per subwoofer. Mounting depth 5 1/2". Type: sealed. Location: FITS BEHIND REAR SEAT; FORWARD FIRING. Maker notes: REMOVAL OF AIR DUCTS, FACTORY JACK & BACK PANEL CARPET; 2007 FITS ONLY THE OLD BODY STYLE. The same outside dimensions, volume and mounting depth are printed for these related listings: 10" dual [GS-WCHV210B]; 12" dual [GS-WCHV212B]; 8" dual [GS-WCHVKK28B]; 10" dual [GS-WCHVL7T210B] (L7T variant); 8" dual [GS-WGM28B]; 12" dual [GS-WGM212B]; 8" dual [GS-WGMKK28B]; 8" triple [GS-WCHV38B]; 10" triple [GS-WCHV310B]; 10" triple [GS-WCHVL7T310B] (L7T variant); 8" triple [GS-WGM38B]; 10" triple [GS-WGM310B]; 10" triple [GS-GML7T310B] (L7T variant); 12" triple [GS-WCHV312B]; 10" dual [GS-WGM210B]; 10" dual [GS-WGML7T210B] (L7T variant); 12" triple [GS-WGM312B].
Ground Shaker (sealed) off-the-shelf
BLACK 8" DUAL SEALED SUB BOX, FITS 99-06 & 07 CLASSIC CHEVY SILVERADO EXT-CAB (SKU GS-NCHV28B). Ground Shaker states fit years 99-06 & 07 CLASSIC for Chevy Silverado Ext-Cab. Published outside dimensions: Height 8 1/4", Length 54 1/4", Depth 13 1/2" (labelled by Ground Shaker). Published volume: 1.78 FT^3 total; 0.89 FT^3 per subwoofer. Mounting depth 6 3/4". Type: sealed. Location: FITS UNDER REAR SEAT; UPWARD FIRING. Maker notes: 2007 FITS ONLY OLD BODY STYLE; WILL NOT FIT TRUCKS WITH V SHAPE HUMP (USE JCHV MODELS FOR V SHAPE HUMP). The same outside dimensions, volume and mounting depth are printed for these related listings: 10" dual [GS-NCHV210B]; 12" dual [GS-NGM212B]; 8" dual [GS-NGMKK28B] (SoloBaric variant); 10" dual [GS-NGMKK210B] (SoloBaric variant); 12" dual [GS-NGMKK212B] (SoloBaric variant); 12" dual [GS-NCHV212B]; 8" dual [GS-NCHVKK28B] (SoloBaric variant); 10" dual [GS-NCHVKK210B] (SoloBaric variant); 8" dual [GS-NGM28B]; 10" dual [GS-NGM210B].
Ground Shaker (sealed) off-the-shelf
BLACK 8" DUAL SEALED SUB BOX, FITS 99-06 CHEVY SILVERADO REGULAR-CAB TRUCKS (SKU GS-STCHV28B). Ground Shaker states fit years 99-06 for Chevy Silverado Regular-Cab Trucks. Published outside dimensions: Height 16 1/4", Length 48 1/4", Top Depth 5 1/2", Bottom Depth 9 1/2" (labelled by Ground Shaker). Published volume: 2.40 FT³ total; 1.20 FT³ per subwoofer. Mounting depth 7". Type: sealed. Location: FITS BEHIND SEAT; FORWARD FIRING. Maker notes: SUBWOOFERS WITH WIDE BASKETS/MAGNETS MAY NOT FIT; CENTER CONSOLE MAY NEED TO BE REMOVED DURING INSTALLATION. The same outside dimensions, volume and mounting depth are printed for these related listings: 10" dual [GS-STCHV210B]; 12" dual [GS-STCHV212B]; 8" triple [GS-STCHV38B]; 10" triple [GS-STCHV310B]; 12" triple [GS-STCHV312B]; 8" triple [GS-STCHVKK38B] (SoloBaric variant); 10" triple [GS-STCHVKK310B] (SoloBaric variant); 12" triple [GS-STCHVKK312B] (SoloBaric variant); 10" triple [GS-STGM310B]; 12" triple [GS-STGM312B]; 8" triple [GS-STGMKK38B] (SoloBaric variant); 10" triple [GS-STGMKK310B] (SoloBaric variant); 8" dual [GS-STCHVKK28B] (SoloBaric variant); 10" dual [GS-STCHVKK210B] (SoloBaric variant); 12" dual [GS-STCHVKK212B] (SoloBaric variant); 8" dual [GS-STGMKK28B] (SoloBaric variant); 10" dual [GS-STGMKK210B] (SoloBaric variant); 12" dual [GS-STGMKK212B] (SoloBaric variant); 8" dual [GS-STGM28B]; 10" dual [GS-STGM210B]; 12" dual [GS-STGM212B]; 8" triple [GS-STGM38B]; 12" triple [GS-STGMKK312B] (SoloBaric variant).
Ground Shaker (sealed) off-the-shelf
BLACK 8" SINGLE SEALED SUB BOX, FITS 99-06 & 07 CLASSIC CHEVY SILVERADO EXT-CAB (SKU GS-NCHV18B). Ground Shaker states fit years 99-06 & 07 CLASSIC for Chevy Silverado Ext-Cab. Published outside dimensions: Height 8 1/4", Length 32 1/4", Depth 13 3/4" (labelled by Ground Shaker). Published volume: 0.75 CUBIC FT^3. Mounting depth 6 11/16". Type: sealed. Location: FITS UNDER REAR SEAT; UPWARD FIRING. Maker notes: 2007 FITS ONLY OLD BODY STYLE. The same outside dimensions, volume and mounting depth are printed for these related listings: 8" single [GS-NCHVKK18B] (SoloBaric variant); 10" single [GS-NCHVKK110B] (SoloBaric variant); 8" single [GS-NGM18B]; 10" single [GS-NCHV110B]; 12" single [GS-NCHVKK112B] (SoloBaric variant); 10" single [GS-NGM110B]; 12" single [GS-NGM112B]; 10" single [GS-NGMKK110B] (SoloBaric variant); 12" single [GS-NCHV112B]; 8" single [GS-NGMKK18B] (SoloBaric variant).
Ground Shaker (2 x 10", ported) off-the-shelf
BLACK 10" DUAL PORTED SOLO-BARIC SUB BOX, FITS 99-06 & 07 CLASSIC CHEVY SILVERADO EXT-CAB (SKU GS-NCHVPK210B). Ground Shaker states fit years 99-06 & 07 CLASSIC for Chevy Silverado Ext-Cab. Published outside dimensions: Height 8 1/4", Length 54 1/4", Depth 13 1/2" (labelled by Ground Shaker). Published volume: 1.62 CUBIC FT. total; 0.81 CUBIC FT. per subwoofer. Mounting depth 7". Type: ported. Location: FITS UNDER REAR SEAT; UPWARD FIRING. Maker notes: L7Q SUBWOOFER WILL NOT FIT; 2007 FITS ONLY OLD BODY STYLE; WILL NOT FIT TRUCKS WITH V SHAPE HUMP (USE JCHV MODEL BOX FOR V SHAPE HUMP).
Ground Shaker (1 x 10", sealed) off-the-shelf
BLACK 10" SINGLE SEALED SUB BOX, FITS 01-17 CHEVY SILVERADO CREW-CAB (SKU GS-QCHV110B). Ground Shaker states fit years 01-17 for Chevy Silverado Crew-Cab. Of the 1999-2006 model years here, it covers 2001-2006 only. Published outside dimensions: Height 6 1/2", Length 30 1/2", Depth 12 1/2" (labelled by Ground Shaker). Published volume: 0.68 FT^3. Mounting depth 5 1/2". Type: sealed. Location: FITS UNDER REAR SEAT; UPWARD FIRING. Maker notes: REQUIRES REMOVAL OF BOLTS PLASTIC COVERS; 2007 FITS ONLY THE OLD BODY ESTYLE.
Ground Shaker (sealed) off-the-shelf
BLACK 10" TW3 DUAL SEALED SUB BOX, FITS 99-06 & 07 CLASSIC CHEVY SILVERADO EXT-CAB (SKU GS-NCHVTW3210B). Ground Shaker states fit years 99-06 & 07 CLASSIC for Chevy Silverado Ext-Cab. Published outside dimensions: Height 8 1/4", Length 54 1/4", Depth 13 1/2" (labelled by Ground Shaker). Published volume: 1.78 FT³ total; 0.89 FT³ per subwoofer. Mounting depth 6 1/2". Type: sealed. Location: FITS UNDER REAR SEAT; UPWARD FIRING. Maker notes: 2007 FITS ONLY OLD BODY STYLE; WILL NOT FIT TRUCKS WITH V SHAPE HUMP (USE JCHV MODELS FOR V SHAPE HUMP). The same outside dimensions, volume and mounting depth are printed for these related listings: 12" dual [GS-NCHVTW3212B] (TW3 variant); 12" dual [GS-NGMTW3212B] (TW3 variant); 10" dual [GS-NGMTW3210B] (TW3 variant).
Ground Shaker (2 x 12", sealed) off-the-shelf
BLACK 12" DUAL SEALED SOLO-BARIC SUB BOX, FITS 99-06 & 07 CLASSIC CHEVY SILVERADO EXT-CAB (SKU GS-NCHVKK212B). Ground Shaker states fit years 99-06 & 07 CLASSIC for Chevy Silverado Ext-Cab. Published outside dimensions: Height 8 1/4", Length 54 1/4", Depth 13 1/2" (labelled by Ground Shaker). Published volume: 1.60 CUBIC FT. total; 0.80 CUBIC FT. per subwoofer. Mounting depth 7 7/8". Type: sealed. Location: FITS UNDER REAR SEAT; UPWARD FIRING. Maker notes: 2007 FITS ONLY OLD BODY STYLE; WILL NOT FIT TRUCKS WITH V SHAPE HUMP (USE JCHV MODEL BOX FOR V SHAPE HUMP); CUT OUT WILL NOT WORK WITH OLD MODEL L7'S.
Ground Shaker (1 x 12", sealed) off-the-shelf
BLACK 12" SINGLE SEALED SOLOBARIC SUB BOX, FITS 99-06 & 07 CLASSIC GMC SIERRA EXT-CAB (SKU GS-NGMKK112B). Ground Shaker states fit years 99-06 & 07 Classic for GMC Sierra Ext-Cab. Published outside dimensions: Height 8 1/4", Length 32 1/4", Depth 13 3/4" (labelled by Ground Shaker). Published volume: 0.75 CUBIC FT^3. Mounting depth 6 3/4". Type: sealed. Location: FITS UNDER REAR SEAT; UPWARD FIRING. Maker notes: 2007 FITS ONLY OLD BODY STYLE.
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
99-06 (2007 Classic) Silverado Extended Cab Single Sub BOX (SKU CHEVY GM EC 99-06 SINGLE). Sound Off Audio states fit years 1999-2006 (also fits 2007 Old Classic Body Style) for Chevrolet Silverado Extended Cab. No outside dimensions on the product page. Published volume: 0.7 cu ft (8" and 10" subs); 0.9 cu ft (12" sub). Mounting depth 7 inches (8" and 10" subs); 6.75 inches (12" sub). Subwoofers: Single subwoofer; fits 8, 10, or 12 inch. Location: Under rear seat. Sound Off Audio also lists the same box as: 'Single Sub Box 1999-2006 GM SIERRA EXTENDED CAB' (gmec9906 single).
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
1999-2006 & 07 CLASSIC SILVERADO EXTENDED CAB SUB BOXES-PAIR (SKU CHEVY GM EC 99-06 DUAL PAIR). Sound Off Audio states fit years 1999-2006 & 2007 (old body style) for Chevy Silverado and GMC Sierra Extended Cab. No outside dimensions on the product page. Published volume: 0.7 cubic feet per subwoofer. Mounting depth 7 inches. Subwoofers: Holds two 8, 10, or 12-inch subwoofers. Location: Fires down. Sound Off Audio also lists the same box as: 'Pair of Single Sub Boxes 1999-2006 GM SIERRA EXTENDED CAB' (GMEC9906 DUAL PAIR).
Sound Off Audio (4 x 8", ported) off-the-shelf
1999-2006 Silverado Ext. Cab Quad 8" Vented Box (SKU gmec998.4v). Sound Off Audio states fit years 1999-2006 for Silverado/Sierra extended cab. No outside dimensions on the product page. Type: Vented. Subwoofers: 4x 8". Location: Under seat.
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
1999-2006 SILVERADO EXTENDED CAB QUAD SUB BOX (SKU CHEVY GM 99-06 QUAD). Sound Off Audio states fit years 1999-2006 for Chevrolet and GMC Sierra Extended Cab. No outside dimensions on the product page. Published volume: 1.3 cubic feet per box (2.6 cubic feet total for pair). Mounting depth 6.5 inches. Subwoofers: Four subwoofers total - either four 8-inch or four 10-inch. Location: Subwoofers fire down. Sound Off Audio also lists the same box as: 'QUAD 10 inch Sub Box 1999-2006 GM SIERRA EXTENDED CAB' (GMEC9906 QUAD SUB BOX).
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
2003-2006 CHEVROLET SILVERADO 1500 CREW Triple sub box (SKU GMCRW01-06 1/2 BTS TRIPLE). Sound Off Audio states fit years 2003-2006 for Chevrolet Silverado 1500 Crew Cab / GMC Sierra 1500 Crew Cab. Of the 1999-2006 model years here, it covers 2003-2006 only. No outside dimensions on the product page. Published volume: 0.65 cubic ft per sub. Mounting depth 5.25 inches. Subwoofers: Triple (3) - fits 8, 10, and 12 inch subwoofers. Location: Behind the rear seat. Sound Off Audio also lists the same box as: 'Triple Sub Box 2003-2006 GM Sierra 1/2 Ton Crew' (GMCRW 1/2 BTS TRIPLE).
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
2003-2006 Chevy Silverado 1/2 TON-SINGLE SUB BOX (SKU GMCHEVY 1500 03-06 SINGLE UTS). Sound Off Audio states fit years 2003-2006 for Chevrolet Silverado 1500 (1/2 ton) crew; GMC Sierra 1/2 ton crew. Of the 1999-2006 model years here, it covers 2003-2006 only. No outside dimensions on the product page. Published volume: 0.5 cu ft per sub. Mounting depth 5.5 inches. Subwoofers: One 8-inch or 10-inch subwoofer. Location: Under rear seat on driver's side. Sound Off Audio also lists the same box as: 'Single Sub Box 2003-2006 GM Sierra 1/2 ton Crew' (GMCRW 1/2 UTS SINGLE).
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
2003-2006 CHEVY SILVERADO Half TON CREW Dual Sub Box (SKU CHEVY GM 1500 CREW DUAL BTS). Sound Off Audio states fit years 2003-2006 for Chevrolet Silverado 1/2 ton crew cab; GMC Sierra 1/2 ton crew cab. Of the 1999-2006 model years here, it covers 2003-2006 only. No outside dimensions on the product page. Published volume: 0.8 cubic feet per chamber. Mounting depth 5.25 inches. Subwoofers: Dual 8s or dual 10s. Location: Behind rear seat. Sound Off Audio also lists the same box as: 'Dual Sub Box 2003-2006 GM Sierra 1/2 ton Crew' (GMCRW 1/2 BTS DUAL).
Sound Off Audio (2 x 12", other (sealed/ported not stated by the maker)) off-the-shelf
DUAL 12 SPEAKER BOX 2001-2006 Chevy Silverado 1500 Crew cab and GMC Sierra 1500 Crew (non heavy duty series) (SKU GMCRW 1/2 BTS 12.2). Sound Off Audio states fit years 2001-2006 for Chevy Silverado 1500 Crew cab and GMC Sierra 1500 Crew (non heavy duty series). Of the 1999-2006 model years here, it covers 2001-2006 only. No outside dimensions on the product page. Published volume: 0.7 cubic foot per chamber. Mounting depth 5.25 inches. Subwoofers: Dual 12 inch subwoofers. Location: Behind rear seat.
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
Dual Sub Box 1999-2006 & 2007 CLASSIC SILVERADO EXTENDED CAB (SKU CHEVY GM EC 99-06 DUAL). Sound Off Audio states fit years 1999-2006 (also fits 2007 old body style) for Chevrolet Silverado / GMC Sierra Extended Cab. No outside dimensions on the product page. Published volume: 1 cu ft per chamber (2 cu ft total). Mounting depth 6.75 inches for dual 12s; 7 inches for dual 10s. Subwoofers: Two 8-inch, two 10-inch, or two 12-inch subwoofers. Location: Under rear seat. Sound Off Audio also lists the same box as: 'Dual Sub Box 1999-2006 GM SIERRA EXTENDED CAB' (GMEC9906 DUAL).
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
DUAL SUB BOX Amp Rack 1999-2006 CHEVY EXTENDED CAB (SKU GMCHEVYEC 99-06 DUAL W/AMP RACK). Sound Off Audio states fit years 1999-2006 for Chevrolet Silverado Extended Cab. No outside dimensions on the product page. Published volume: 1.3 cu ft for the whole box. Mounting depth 6.75 inches (dual 12), 7 inches (dual 10). Subwoofers: Two 8 inch, two 10 inch, or two 12 inch subwoofers. Location: Under rear seat. Sound Off Audio also lists the same box as: 'Dual Sub Box w/AMP RACK 1999-2006 GM SIERRA EXTENDED CAB DUAL SUB BOX AMP RACK' (GMEC9906 DUAL AMP RACK).
Sound Off Audio (other (sealed/ported not stated by the maker)) off-the-shelf
DUAL SUB BOX for 2003-2006/07 Classic Chevy Silverado 1500 CREW (SKU GMCHEVY 1500 CREW 03-06 DUAL UTS). Sound Off Audio states fit years 2003-2006/07 for Chevrolet Silverado or GMC Sierra 1500 (1/2 ton), Non-HD Crew Cab. Of the 1999-2006 model years here, it covers 2003-2006 only. No outside dimensions on the product page. Published volume: 0.5 cubic ft per sub. Mounting depth 5.125 inches. Subwoofers: Dual 8 or dual 10 subwoofers. Location: Under the rear seat.
Sound Off Audio (ported) off-the-shelf
Ported box 1999-2006 CHEVY SILVERADO EXTENDED CAB (SKU CHEVY GM EC 99-06 PORTED LG). Sound Off Audio states fit years 1999-2006 for Chevrolet Silverado Extended Cab; GMC Sierra Extended Cab. No outside dimensions on the product page. Published volume: 1.1 cubic ft per sub. Mounting depth 7 inches. Type: Ported. Subwoofers: Dual 8 or 10 inch subwoofers. Location: Under rear seat. Sound Off Audio also lists the same box as: 'PORTED DUAL SUB BOX 1999-2006 GM SIERRA EXTENDED CAB' (GMEC9906 PORTED).
Sound Off Audio (2 x 8", ported) off-the-shelf
PORTED DUAL 8 BOX 1999-2006 CHEVY SILVERADO EXTENDED CAB (SKU PORT GMEC99 8.2 sm). Sound Off Audio states fit years 1999-2006 for Chevrolet Silverado and GMC Sierra Extended Cabs. No outside dimensions on the product page. Published volume: 1.7 cubic ft (total). Mounting depth 7 inches. Type: Ported/Vented. Subwoofers: Dual 8 inch. Location: Choice of either side of rear seat. Sound Off Audio also lists the same box as: 'PORTED DUAL 8 BOX - 1999-2006 GMC SIERRA EXTENDED CAB' (PORT GMEC99 DUAL 8 sm).
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab 2001-2006 Dual 12" BTS Subwoofer Box (SKU 01ChevyCCbtsdual12). Super Crew Sound states fit years 2001-2006 for Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab. Of the 1999-2006 model years here, it covers 2001-2006 only. No outside dimensions on the product page. Published volume: .70 cubic foot per sub. Mounting depth 5 1/4" (Optional 5 7/8"). Subwoofers: Fits two 8, 10 or 12 inch subwoofers. Location: Fits behind the seat. Maker notes: Fits 1/2 ton version only (non-HD); Removal of jack is necessary. Hole cutouts 8" 7", 10" 9 1/8", 12" 11". MDF. The page says to remove the black plastic vents from the rear cab wall.
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab 2001-2006 Dual BTS Subwoofer Box (SKU 01ChevyCCbtsdual). Super Crew Sound states fit years 2001-2006 for Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab. Of the 1999-2006 model years here, it covers 2001-2006 only. No outside dimensions on the product page. Published volume: 0.70 cubic foot per sub. Mounting depth 5 1/4" (Optional 5 7/8"). Type: Sealed (not ported unless added). Subwoofers: Two 8 or 10 inch subwoofers. Location: Behind the seat. Maker notes: Fits 1/2 ton version only (non-HD); Removal of jack is necessary. Hole cutouts 8" 7", 10" 9 1/8". MDF.
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab 2001-2006 Single BTS Subwoofer Box (SKU 01ChevyCCbtssingle). Super Crew Sound states fit years 2001-2006 for Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab. Of the 1999-2006 model years here, it covers 2001-2006 only. No outside dimensions on the product page. Published volume: 0.70 cubic foot Per Sub. Mounting depth 5 1/4" (Optional 5 7/8"). Subwoofers: One 8 or 10 inch subwoofer. Location: Behind the seat. Maker notes: Fits 1/2 ton version only (non-HD). Hole cutouts 8" 7", 10" 9 1/8".
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab 2001-2006 Single UTS Subwoofer Box (SKU 01ChevyCCutssingle). Super Crew Sound states fit years 2001-2006 for Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab. Of the 1999-2006 model years here, it covers 2001-2006 only. No outside dimensions on the product page. Published volume: .55 cubic foot Per Sub. Mounting depth 5 1/2". Subwoofers: one 8 or 10 inch subwoofer. Location: under the seat (Driver's side). Maker notes: Fits 1/2 ton version only (non-HD). Mounting depth based on 6" diameter magnet. Hole cutouts 8" 7", 10" 9 1/8". MDF.
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab 2003-2006 Dual UTS Subwoofer Box (SKU 03ChevyCCutsdual). Super Crew Sound states fit years 2003-2006 for Chevy Silverado / GMC Sierra 1/2 Ton Crew Cab. Of the 1999-2006 model years here, it covers 2003-2006 only. No outside dimensions on the product page. Published volume: 0.50 cubic foot per sub. Mounting depth 5 1/8". Subwoofers: Two 8 or 10 inch subwoofers. Location: Under the seat; Subwoofers fire up. Maker notes: Fits 1/2 ton version only (non-HD). Hole cutouts 8" 7", 10" 9 1/8".
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra Extended Cab 1999-2006 Dual Subwoofer Box (SKU 99ChevyECdual). Super Crew Sound states fit years 1999-2006 for Chevy Silverado / GMC Sierra Extended Cab. No outside dimensions on the product page. Published volume: 0.85 cubic foot per sub. Mounting depth 6 1/4" (8" & 10"); Optional 6 7/8"; 6" (12"); Optional 6 5/8". Subwoofers: 2 subwoofers, fits 8, 10, or 12 inch. Location: Fits under rear seat; Subs fire down. Maker notes: Will fit 2007 Classic. 1 1/4" under box clearance. Box divider and speaker terminals included. Hole cutouts 8" 7", 10" 9 1/8", 12" 11".
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra Extended Cab 1999-2006 Pair of Subwoofer Boxes (SKU 99ChevyECpair). Super Crew Sound states fit years 1999-2006 for Chevy Silverado / GMC Sierra Extended Cab. No outside dimensions on the product page. Published volume: .70 cubic foot Per Sub (8" & 10"); .90 cubic foot Per Sub (12"). Mounting depth 7" (8" & 10") (Optional 7 5/8"); 6 3/4" (12") (Optional 7 3/8"). Subwoofers: Fits two 8, 10 or 12 inch subwoofers. Location: Fit under rear seat; Subs fire down. Maker notes: Will fit 2007 Classic; May have to remove floor mats. Hole cutouts 8" 7", 10" 9 1/8", 12" 11".
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra Extended Cab 1999-2006 Quad Subwoofer Box (SKU 99ChevyECquad). Super Crew Sound states fit years 1999-2006 for Chevy Silverado / GMC Sierra Extended Cab. No outside dimensions on the product page. Published volume: 1.30 cubic foot Per Side (.65 per sub). Mounting depth 6 1/4" (Optional 6 7/8"). Subwoofers: Fits Four 8 or 10 inch subwoofers. Location: Fits under rear seat; Subs fire down. Maker notes: Will fit 2007 Classic. Max subwoofer overall diameter 10.25". Box construction: MDF, two pieces, 58" (as printed). 1 1/4" clearance under the box. Box divider and speaker terminals included. Hole cutouts 8" 7", 10" 9 1/8", 12" 11".
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Silverado / GMC Sierra Extended Cab 1999-2006 Single Subwoofer Box (SKU 99ChevyECsingle). Super Crew Sound states fit years 1999-2006 for Chevy Silverado / GMC Sierra Extended cab. No outside dimensions on the product page. Published volume: .70 cubic foot (8" & 10"); .90 cubic foot (12"). Mounting depth 7" (8" & 10") (Optional 7 5/8"); 6 3/4" (12") (Optional 7 3/8"). Type: One Round Tube Port (optional, +$29). Subwoofers: Fits one 8, 10 or 12 inch subwoofer. Location: Fits under rear seat; Sub fire down. Maker notes: Will fit 2007 Classic; May have to remove floor mats. 1 1/4" clearance under the box. Hole cutouts 8" 7", 10" 9 1/8", 12" 11". MDF.
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Standard Cab 06 and Down Single Subwoofer Box (SKU ChevyStdsingle). Super Crew Sound states fit years "06 and Down" (no start year) for the Chevy Silverado Standard Cab. No outside dimensions on the product page. Published volume: .7 cubic feet per sub. Mounting depth 5.5" (Optional 6 1/8" available). Subwoofers: Fits one 8, 10 or 12 inch subwoofer. Location: Fits behind seat. Hole cutouts 8" 7", 10" 9 1/8", 12" 11". MDF.
Super Crew Sound (other (sealed/ported not stated by the maker)) off-the-shelf
Chevy Standard Cab 2006 and Down Dual Subwoofer Box w/ Amp Rack (SKU ChevyStddual). Super Crew Sound states fit years "2006 and down" (no start year) for the Chevy Silverado Standard Cab. No outside dimensions on the product page. Published volume: 0.7 cubic feet per sub. Mounting depth 5.5" (Optional 6 1/8" available). Subwoofers: Fits two 8, 10 or 12 inch subwoofers. Location: Fits behind seat. Hole cutouts 8" 7", 10" 9 1/8", 12" 11". MDF.

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