Factory setup not specified in fitment source

2003 Lexus GS300 Headlight Bulbs & Lighting Guide

Choose the factory headlight system below to see the correct bulb and recommendation path for this 2003 Lexus GS300.

Low beam
9006 / HB4
High beam
9005 / HB3
Factory setup
Factory setup not specified in fitment source

Choose the factory system installed in this vehicle. Bulb sizes and recommendations change with that selection.

2003 Lexus GS300 representative vehicle image

Best headlight upgrades

These products were physically tested by BulbFacts, but the tests were not performed in this exact vehicle unless a card explicitly says otherwise.

Factory setup not specified in fitment source

Low Beam: 9006 / HB4 · High Beam: 9005 / HB3

Best direct replacement

OSRAM Night Breaker 200

Low Beam 9006 / HB4 · High Beam 9005 / HB3

BulbFacts testedCorrect bulb size
Best Standard Reflector Upgrade

The Night Breaker 200 is the top standard-wattage reflector recommendation at the time of review. Anything scoring higher in the reflector chart uses much higher wattage, while the NB200 keeps the simple drop-in halogen format.

General BulbFacts housing test
Read BulbFacts reviewCompare test resultsBuy at eBay

A matching bulb size identifies fitment; it does not by itself prove optical compatibility or make a conversion a vehicle-specific recommendation.

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Other bulbs

Available exterior and interior lighting data for this model year.

Ashtray Light
T5Possible fitment — verify installed bulb
Brake Light
7443Possible fitment — verify installed bulb
Cargo / Trunk Light
T10Possible fitment — verify installed bulb
Center High Mount Stop Light
T10Possible fitment — verify installed bulb
Courtesy Light
DE3175Possible fitment — verify installed bulb
Dome Light
DE3175Possible fitment — verify installed bulb
Fog Light
9006 / HB4Possible fitment — verify installed bulb
Front Side Marker
T10Possible fitment — verify installed bulb
Front Turn Signal
7443Possible fitment — verify installed bulb
Glove Box Light
T5Possible fitment — verify installed bulb
Instrument Panel Light
T5Possible fitment — verify installed bulb
License Plate Light
T10Possible fitment — verify installed bulb
Technical details and sources

Fitment, factory-system research, and BulbFacts product tests remain separate evidence. A matching bulb size does not by itself make a conversion a vehicle-specific recommendation.

PositionBulb or systemEvidence status
Low BeamFactory setup not specified in fitment source9006 / HB4Possible fitment — verify installed bulb
High BeamFactory setup not specified in fitment source9005 / HB3Possible fitment — verify installed bulb
Low BeamLighting: HIDD2RLikely fitment

Each model year opens its own BulbFacts record. Bulb sizes and factory systems are not carried over from adjacent years.

Fitment note: Verify the installed bulb, connector, housing, and factory system before ordering. A bulb-size match is not automatically a conversion recommendation or proof of vehicle-specific testing.