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 Sedan
These are researched envelopes, not a guarantee. Measure your own vehicle — the numbers here tell you what to expect, not what you have.
| Location | trunk |
|---|---|
| Outer bounding box | No independently measured trunk dimensions found. Vehicle-specific enclosure catalogues; published box footprints are lower bounds on the cavity, not the cavity: NET Audio '2005-2007 Lexus GS300 Sub Box Sealed' and '...Ported': 30.5 x 12 x 14.75 in (as printed; axes not labelled), 1.88 cu ft, trunk, against the rear trunk wall [only 2006-2007 fall in this generation]. Zenclosures 'Lexus 2007-2011 Gs Gs350 Gs460 Subwoofer Box': no outside dimensions, 1.08 ft3 per chamber, 10.00" mounting depth. |
| Known obstructions | NET Audio: a 15" sub will not fit; the page says the box "barely" fits at 16" deep. The factory Mark Levinson subwoofer and front woofers need summing for full bass (NET Audio's statement, GS 300). |
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 | Lexus's GS material gives a Mark Levinson speaker count (14), not sizes or positions |
|---|---|
| Adapter bracket needed | unconfirmed |
| Factory speaker size | same gap as the front doors |
|---|---|
| Adapter bracket needed | unconfirmed |
| Factory amp / premium audio | Lexus, GS (2010 and 2011 models): optional Mark Levinson Premium Surround Sound, "330 watts" on the GS, 14 speakers including a center speaker and a subwoofer, 7.1-channel architecture. The standard GS system, speaker sizes and the position of the factory subwoofer were not found. 2006-2009 not read. |
|---|---|
| Adding subs without a head-unit swap | NET Audio (GS 300, 2005-2007 box pages, vendor statement): with the Mark Levinson system "you need to use some sort of signal summing device using the factory sub and the front woofers" to get full bass. Nothing Lexus-published was found. |
Three sealed or ported boxes fit the trunk: Zenclosures 1.08 ft3 per chamber at 10.00" depth, and NET Audio's dual rear-fire 30.5 x 12 x 14.75 in (axes unlabelled) box at 1.88 cu ft and 8.375" depth, which sits against the rear trunk wall. EPA's luggage figure is 13 cu ft for the conventional sedans (the GS 450h hybrid 8-9), a government rating and not a Lexus figure or a box dimension. No measured trunk dimensions were found. NET Audio warns that the factory Mark Levinson system needs a signal-summing device to keep the factory sub and front woofers in the mix. The 13 cu ft applies to the conventional GS 300, 350, 430 and 460 only, not the GS 450h hybrid, and no box here names the hybrid. Measure your own trunk before cutting wood.
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.