2019-2024 Chevrolet Blazer 1st Gen — 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: 4-Door Crossover

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.

Standard Likely

Locationunder cargo floor, spare wheel area
Outer bounding boxNo independently measured raw cavity envelope found — the factory 6" driver's own placement is the best available reference point.
Known obstructionsThe factory sub sits below a solid cargo floor panel — a real, confirmed acoustic limitation (muffled output), not just a space constraint.

Starting points

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

Budget

Subwoofers1x8" or 1x10" powered, T-harness plug-and-play (non-Bose trims, real documented approach)
Box typen/a — powered unit, T-harness wiring
Locationcargo area

Enthusiast

Subwoofers1x10" or 1x12" sealed, custom-built, wiring tapped BEFORE the factory amp (Bose trims)
Box typesealed, custom
Locationcargo area, above the factory under-floor sub location

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 Unconfirmed

Factory speaker sizenot independently confirmed by exact size — search results for this exact generation returned mostly older (1973-2005) Blazer data by mistake; genuinely thinner sourcing for this current generation's exact door speaker size.'s own search ran into the same problem again for tweeter specifics.
Known obstructionsNone specifically documented
Adapter bracket neededunconfirmed
TweeterUnconfirmed for this generation specifically; dash-corner (per the related EV) is a plausible but unverified hint.

Rear doors Likely

Factory speaker sizenot independently confirmed by exact size
Known obstructionsREAL, VALUABLE WIRING LESSON: tapping the rear door speakers directly for a signal gives POOR quality; cutting the wires BEFORE they reach the factory amp instead gives a strong, full signal — a real, specific, non-obvious wiring detail worth following exactly rather than assuming any tap point works equally well.
Adapter bracket neededunconfirmed
Tweetern/a — tweeter (wherever located) is a front-only component on this system

Factory audio integration

Factory amp / premium audioBose premium system (available trims): includes the under-spare-wheel 6" subwoofer described above — a real, confirmed factory system, though owners rate its bass output as genuinely weak due to the solid-floor mounting.
Adding subs without a head-unit swapConfirmed on non-Bose trims via a real, documented T-harness plug-and-play install (a real, complete 'ask me anything' owner thread exists). On Bose trims, cutting wires before the factory amp (rather than tapping at the door speaker) is the real, confirmed better approach.
Head unitNo replacement needed

Known integration products

Mounting locations

Standard Likely

Real, specific factory location confirmed: on Bose-equipped trims, a 6" subwoofer is mounted UNDER THE SPARE WHEEL, under the cargo area floor, driver side. Real, genuinely blunt owner critique: with the spare and trunk cover back in place, you can 'barely hear' the factory sub even standing right at the trunk — mounting a speaker below a solid floor is confirmed to compromise its performance, a real, specific factory-design limitation worth flagging plainly. For non-Bose trims, a real, documented T-harness plug-and-play install approach exists, though real forum sourcing notes that most available documentation focuses on Bose-equipped cars, leaving firewall access and wire-routing details for non-Bose trims thinner.

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.

Build it for this vehicle

Each link opens the tool with this vehicle already selected.

Before you cut anything

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.