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DS18 PRO-ZXI10MBASS (Sold Individually)

1000W Peak (500W RMS) 10" ZXi Series 8-Ohm Midbass Car Loudspeaker

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1000W Peak (500W RMS) 10" ZXi Series 8-Ohm Midbass Car Loudspeaker

• 1000 watts Peak Each, 500 watts RMS Each
• Paper cone material
• Impedance: 8 ohm
• Sensitivity: 98 dB

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Install kits available for most vehicles

found car based on your search
Fits your GS400
$149.95

In stock.

• 1000 watts Peak Each, 500 watts RMS Each
• Paper cone material
• Impedance: 8 ohm
• Sensitivity: 98 dB

DS18 EXL-SQ4.0

520W Peak (120W RMS) 4" EXL Series 2 Way Coaxial 3-ohm Speakers

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520W Peak (120W RMS) 4" EXL Series 2 Way Coaxial 3-ohm Speakers

• 260 watts Peak Each, 60 watts RMS Each
• 1" PEI (Polyetherimide) Dome Tweeters
• Fiberglass cone material
• Impedance: 3 ohm
• Sensitivity: 85 dB

1+ offers available
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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
$119.95 /pair

In stock

Continue to cart

Available Offers (2) for DS18 EXL-SQ4.0
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Flash Sale! Save at Checkout!
$119.95
$101.96 with coupon | Price details
Free Speaker Accessory at Checkout!
Limited time!

Diamond Audio DMD42

120W Peak (60W RMS) 4" DMD Series 2 Way Coaxial 4-ohm Speakers

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120W Peak (60W RMS) 4" DMD Series 2 Way Coaxial 4-ohm Speakers

• 60 watts Peak Each, 30 watts RMS Each
• 3/4" Silk Dome Tweeters
• Reinforced Polypropylene cone material
• Impedance: 4 ohm
• Sensitivity: 84 dB

Free Speaker Accessory at Checkout!
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VIP Product Get $11.00 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
List price $119.99
-8% $109.99 /pair

In stock.

Limited time!

Alpine S2-S40C

280W Peak (90W RMS) 4" S-Series Hi-Res 2-Way Component Car Speakers

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280W Peak (90W RMS) 4" S-Series Hi-Res 2-Way Component Car Speakers

• 140 watts Peak Each, 45 watts RMS Each
• Hi-Res Audio Certified
• 1" Cloth Dome Tweeters
• Adjustable tweeters with threaded removable housing
• Polypropylene, Glass Fiber and Mica cone material
• Impedance: 4 ohm
• Sensitivity: 86 dB

Free Speaker Accessory at Checkout!
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VIP Product Get $15.00 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
1
List price $180.00
-17% $149.95 /set

In stock

Diamond Audio DMDX4

180W Peak (60W RMS) 4" DMD Series 2-Way Cocentric Coaxial 4-ohm Speakers

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180W Peak (60W RMS) 4" DMD Series 2-Way Cocentric Coaxial 4-ohm Speakers

• 90 watts Peak Each, 30 watts RMS Each
• Dome Tweeters
• Treated Paper cone material
• Impedance: 4 ohm
• Sensitivity: 82 dB

shipping truck icon Free shipping in USA. Provide zip for delivery date.
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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
$109.99 /pair

In stock.

Limited time!

Pioneer TS-G1020S

420W Peak (60W RMS) 4" G-Series 2-way 4-ohm Coaxial Car Speakers

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420W Peak (60W RMS) 4" G-Series 2-way 4-ohm Coaxial Car Speakers

• 210 watts Peak Each, 30 watts RMS Each
• 1-3/16" Polyethylene Terephthalate (PET) Balanced Dome tweeters
• Mica Injected Polypropylene - MIPP cone material
• Impedance: 4 ohm
• Sensitivity: 87 dB

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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
2
List price $65.00
Save 25%
-25% $48.99 /pair

In stock

DS18 10OCT500-8 (Sold Individually)

1000W Peak (500W RMS) 10" Octagonal Series 8-ohm Mid-range Speaker

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1000W Peak (500W RMS) 10" Octagonal Series 8-ohm Mid-range Speaker

• 1000 watts Peak Each, 500 watts RMS Each
• Paper cone material
• Impedance: 8 ohm
• Sensitivity: 100 dB

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VIP Product Get $16.50 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits your GS400
$164.95

In stock.

American Bass NEO-10-MR (Sold Individually)

450W Peak (225W RMS) 10" NEO Series Midrange 4-ohm Speaker

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450W Peak (225W RMS) 10" NEO Series Midrange 4-ohm Speaker

• Peak Power: 450 watts
• RMS Power: 225 watts
• Fiber Paper cone material
• Impedance: 4 ohm
• Sensitivity: 98.3 dB

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Install kits available for most vehicles

found car based on your search
Fits your GS400
List price $207.00
-21% $164.35

In stock.

Pioneer TS-A1081F (Open Box, Great)

460W Peak (100W RMS) 4” A Series 2-way 4-ohm Coaxial Car Speakers

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460W Peak (100W RMS) 4” A Series 2-way 4-ohm Coaxial Car Speakers

• 230 watts Peak Each, 50 watts RMS Each
• 1" PEI (Polyetherimide) Hard Dome tweeters
• Carbon and Mica Reinforced Injection Molded Polypropylene cone material
• Impedance: 4 ohm
• Sensitivity: 90 dB

shipping truck icon Free shipping in USA. Provide zip for delivery date.
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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
List price $110.00
-27% $80.00 /pair

In stock

Only 1 Left!

Limited time!

Boss Elite BE423

450W Peak 4" Rage Series 3-Way Coaxial 4-ohm Car Speakers with Blue LED Light

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450W Peak 4" Rage Series 3-Way Coaxial 4-ohm Car Speakers with Blue LED Light

• 225 watts Peak
• 1/2" and 1.25" Piezo Dome Tweeters
• Polypropylene cone material
• Features integrated blue LED illumination
• Impedance: 4 ohm
• Sensitivity: 90 dB

Free Speaker Accessory at Checkout!
shipping truck icon Free shipping in USA. Provide zip for delivery date.
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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
List price $66.99
-18% $54.99 /pair

Available

Ships in 10-14 days

MTX TERMINATOR4

120W Peak (60W RMS) 4" Terminator Series 2-Way Coaxial 4-ohm Car Speakers

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120W Peak (60W RMS) 4" Terminator Series 2-Way Coaxial 4-ohm Car Speakers

• 60 watts Peak Each, 30 watts RMS Each
• Silk Dome Tweeters
• Polypropylene cone material
• Impedance: 4 ohm
• Sensitivity: 88.1 dB

shipping truck icon Free shipping in USA. Provide zip for delivery date.
install icon

Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
List price $64.95
-15% $54.95 /pair

In stock

Only 3 Left!

DS18 G4XI

240W Peak (80W RMS) 4" GEN-X Series 2 Way Coaxial 4-ohm Speakers

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240W Peak (80W RMS) 4" GEN-X Series 2 Way Coaxial 4-ohm Speakers

• 120 watts Peak Each, 40 watts RMS Each
• 1" Mylar Dome Tweeters
• Paper cone material
• Impedance: 4 ohm
• Sensitivity: 84 dB

shipping truck icon Free shipping in USA. Provide zip for delivery date.
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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
List price $55.99
-18% $45.95 /pair

In stock.

Limited time!

Massive Audio MX4

300W Peak (60W RMS) 4" MX Series 2-Way 4-ohm Coaxial Car Speakers

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300W Peak (60W RMS) 4" MX Series 2-Way 4-ohm Coaxial Car Speakers

• 150 watts Peak Each, 30 watts RMS Each
• 1/2" PEI (Polyetherimide) Dome tweeters
• Tweeters constructed with ferro fluid cooled voice coil
• Laminate-Treated Paper cone material
• Impedance: 4 ohm
• Sensitivity: 91.5 dB

Free Speaker Accessory at Checkout!
shipping truck icon Free shipping in USA. Provide zip for delivery date.
install icon

Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
1
List price $49.99
-20% $39.99 /pair

Available

Ships in 10-14 days

DS18 10XL1400-4 (Sold Individually)

1400W Peak (700W RMS) 10" XL Series Midrange 4-ohm Loudspeaker

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1400W Peak (700W RMS) 10" XL Series Midrange 4-ohm Loudspeaker

• 1400 watts Peak, 700 watts RMS
• Non-Pressed Paper cone material
• Impedance: 4 ohm
• Sensitivity: 98 dB

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VIP Product Get $24.00 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits your GS400
List price $287.99
-17% $239.95

In stock

Only 1 Left!

DS18 10XL1400-8 (Sold Individually)

1400W Peak (700W RMS) 10" XL Series Midrange 8-ohm Loudspeaker

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1400W Peak (700W RMS) 10" XL Series Midrange 8-ohm Loudspeaker

• 1400 watts Peak, 700 watts RMS
• Non-Pressed Paper cone material
• Impedance: 8 ohm
• Sensitivity: 98 dB

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VIP Product Get $24.00 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits your GS400
List price $287.99
-17% $239.95

In stock.

DS18 10XL1400MB-4 (Sold Individually)

1400W Peak (700W RMS) 10" XL Series Mid-Bass 4-ohm Loudspeaker

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1400W Peak (700W RMS) 10" XL Series Mid-Bass 4-ohm Loudspeaker

• 1400 watts Peak, 700 watts RMS
• Non-Pressed Paper cone material
• Impedance: 4 ohm
• Sensitivity: 98 dB

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VIP Product Get $24.00 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits your GS400
List price $287.99
-17% $239.95

Available

Ships in 10-14 days

DS18 10XL1400MB-8 (Sold Individually)

1400W Peak (700W RMS) 10" XL Series Mid-Bass 8-ohm Loudspeaker

10XL1400MB-8 big
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1400W Peak (700W RMS) 10" XL Series Mid-Bass 8-ohm Loudspeaker

• 1400 watts Peak, 700 watts RMS
• Non-Pressed Paper cone material
• Impedance: 8 ohm
• Sensitivity: 98 dB

shipping truck icon Free shipping in USA. Provide zip for delivery date.
VIP Star Icon

VIP Product Get $24.00 in rewards to spend later

install icon

Install kits available for most vehicles

found car based on your search
Fits your GS400
List price $287.99
-17% $239.95

In stock.

DS18 PRO-CUPOLA2 (Sold Individually)

300W Peak (100W RMS) 4" Pro Audio Soft Dome Midrange 4-ohm Loudspeaker

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300W Peak (100W RMS) 4" Pro Audio Soft Dome Midrange 4-ohm Loudspeaker

• 300 watts Peak, 100 watts RMS
• Coated non-resonant soft dome material
• Ultra-high sound quality
• Perfect for studio monitors or Hi-Fi applications
• Impedance: 4 ohm
• Sensitivity: 95 dB

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VIP Product Get $10.00 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits multiple locations in your GS400
  • Lower Front Door
  • Rear Door
List price $119.99
-17% $99.95

In stock.

DS18 PRO-1.5KP10.8 (Sold individually)

3000W Peak (1500W RMS) 10" PANCADÃO Series Competition Mid-bass 8-ohm Loudspeaker

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3000W Peak (1500W RMS) 10" PANCADÃO Series Competition Mid-bass 8-ohm Loudspeaker

• 3000 watts Peak, 1500 watts RMS
• Paper cone material
• Impedance: 8 ohm
• Sensitivity: 94 dB

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VIP Product Get $26.40 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits your GS400
1
$263.95

In stock

DS18 PRO-X10M

600W Peak (300W RMS) 10" PRO-X Series 8-ohm Mid-Range Loudspeaker

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600W Peak (300W RMS) 10" PRO-X Series 8-ohm Mid-Range Loudspeaker

• 600 watts Peak Each, 300 watts RMS Each
• Non-Pressed Paper cone material
• Impedance: 8 ohm
• Sensitivity: 96 dB

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VIP Product Get $9.00 in rewards to spend later

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Install kits available for most vehicles

found car based on your search
Fits your GS400
$89.95

In stock

Only 3 Left!

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    FAQ for Speakers in 1999 GS400

    Q: Can I upgrade or change the Speakers in 1999 Lexus GS400?

    A: Yes this page includes all the best Speakers that work in your GS400.

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    Modern vehicles often require specific brackets, wiring harnesses, and mounting solutions. A fit guide ensures:

    • You see only parts engineered for your exact vehicle
    • You avoid incompatible radios, speakers, or wiring
    • Installation is smoother, faster, and frustration-free
    • You get the correct accessories the first time

    Whether you're replacing a factory stereo or upgrading your entire audio system, the Fit Finder eliminates uncertainty.