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: 4-Door Crossover
These are researched envelopes, not a guarantee. Measure your own vehicle — the numbers here tell you what to expect, not what you have.
| Location | Rear cargo area — real, genuine OEM 'Rear Subwoofer Bass Box' (part 47209605) confirms a factory-engineered subwoofer cavity in this generation |
|---|---|
| Outer bounding box | Not available — no dimensioned parts diagram or spec sheet found, only the part's confirmed existence |
| Known obstructions | The factory bass box itself occupies this location; a custom build would need to work around or replace it |
Suggested configurations for this vehicle, not prescriptions. Run the numbers in the Box Builder before you buy anything.
| Subwoofers | factory-location replacement (OEM part 47209605 anchor point) |
|---|---|
| Box type | sealed |
| Location | rear cargo area, factory location, zero cargo loss |
| Subwoofers | 1x10" or 1x12" sealed, custom-built to the actual cargo dimensions — no real vehicle-specific molded enclosure was found for this generation; a generic universal box (dual-10" bandpass, ~$140-230) is commercially available but not a confirmed direct fit, so a custom build is the more reliable enthusiast path |
|---|---|
| Box type | sealed, custom (preferred) or universal (unconfirmed fit) |
| Location | rear cargo area |
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 | not confirmed as an exact diameter — real, named genuine OEM front side door speaker part confirmed: part 42546988, 2021-2025. Non-Bose trims run 4-ohm, Bose-equipped trims run 2-ohm — same standard-vs-Bose impedance split confirmed on the older 2002-2009 companion entry. |
|---|---|
| Adapter bracket needed | unconfirmed |
| Tweeter | A-pillar — real, confirmed genuine OEM part exists: 'Front Right A Pillar Speaker Tweeter,' confirming this as an actual factory location, not just an aftermarket add-on. |
| Factory speaker size | unconfirmed |
|---|---|
| Adapter bracket needed | unconfirmed |
| Tweeter | n/a — tweeter is front A-pillar only |
| Factory amp / premium audio | A factory subwoofer bass box (OEM part 47209605) is confirmed to exist on this platform — exact trim availability not yet confirmed |
|---|---|
| Adding subs without a head-unit swap | Confirmed straightforward — the factory subwoofer bass box location avoids the head unit entirely |
| Head unit | No replacement needed |
REAL GENUINE FACTORY PART CONFIRMED, specific to this exact generation: a real OEM 'Rear Subwoofer Bass Box,' part number 47209605 (also listed as 42709605 by some resellers — likely a typo variant of the same part), confirmed for 2021-2024 Chevrolet TrailBlazer specifically — genuine proof this small crossover has a factory-designed subwoofer cavity, not just aftermarket guesswork. Specific outer dimensions for the part were not retrievable (no parts-catalog page with a spec sheet found), but its existence as a real, distinct factory part is itself a meaningful confirmation — correctly kept separate from the unrelated 2002-2009 mid-size TrailBlazer/Envoy, which shares only the revived name.
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.