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/Double Cab, Crew Cab
These are researched envelopes, not a guarantee. Measure your own vehicle — the numbers here tell you what to expect, not what you have.
| Location | underseat storage compartment, crew cab |
|---|---|
| Outer bounding box | 54"W x 13"D x 6.5"H (rear) tapering up to 9.5"H (front) — sourced from a storage-drawer product explicitly spanning 2007-2018, matching this entry's range |
| Known obstructions | None specifically documented beyond the front-to-rear height taper already in the bounding box |
| Usable volume estimate | 3 ft³ |
Suggested configurations for this vehicle, not prescriptions. Run the numbers in the Box Builder before you buy anything.
| Subwoofers | 1x10" or 1x12" ported, 1.25 ft3 |
|---|---|
| Box type | ported |
| Location | under/behind rear seat |
| Subwoofers | 2x10" or 2x12" (per Stealthbox/other Crew Cab commercial products) |
|---|---|
| Box type | sealed |
| Location | under rear seat |
Sizes and depths below are what research turned up for this generation. Confirm against your own vehicle before cutting or ordering — trim levels vary.
| Factory speaker size | closest aftermarket equivalent is 6-3/4" |
|---|---|
| Known obstructions | Factory speaker is not truly 6-3/4" — an adapter plate is needed for any aftermarket speaker |
| Adapter bracket needed | yes |
| Factory speaker size | closest aftermarket equivalent is 6-3/4" (Crew Cab and Extended/Double Cab both) |
|---|---|
| Known obstructions | Adapter plate needed, same as front |
| Adapter bracket needed | yes |
| Factory amp / premium audio | Real, confirmed on this generation, trim gating partial. 6-CD in-dash Bose system available on top-tier trims — GMC Sierra Denali (continuing this entry's predecessor generation's standard-Bose finding) and select top-of-line Silverado trims (LTZ-level). Exact Silverado trim name/year boundary within 2007-2013 not fully pinned down. |
|---|---|
| Adding subs without a head-unit swap | Confirmed straightforward — multiple commercial direct-fit products exist |
| Head unit | No replacement needed |
Real commercial data, though year-range labeling is inconsistent across sellers and worth flagging rather than smoothing over: one product lists 'GMC Sierra 2007-2014' Crew Cab compatibility while listing 'Chevy Silverado 2014-2018' separately — possibly reflecting a real one-year badge-engineering offset between the two brands, or just imprecise marketing copy. Treat as needing verification, not fact. A JL Audio Stealthbox covers Crew Cab 1500 AND 2500/3500 Crew Cab as one shared part.
Real specific spec found for this body style: single ported 10" or 12", 1.25 ft3, mounting depth 5.75" (10") or 5.5" (12")
Outside links. Some are commercial products, some are owner builds posted on forums — the label says which. We do not endorse any of them.
Each link opens the tool with this vehicle already selected.
Measure your own vehicle. Trim levels, factory subwoofer options, and mid-generation changes all move these numbers, and a box cut to a researched figure that does not match your truck is wasted wood. Where a badge reads Unconfirmed, treat the value as a starting point for your own measurement, not as an answer.