What is the low beam headlight bulb size for a 1991 Geo Metro?

The 1991 Geo Metro uses a H4666 bulb for the low beam headlights. We recommend upgrading to LED for better visibility.

What is the high beam headlight bulb size for a 1991 Geo Metro?

The high beam bulb size for the 1991 Geo Metro is N/A.

Why are my 1991 Geo Metro headlights dim?

Dim headlights on a 1991 Geo Metro can be caused by aging halogen bulbs, which lose brightness over time, or oxidation (cloudiness) on the plastic headlight lenses. Upgrading to a H4666 LED conversion kit can provide a significantly brighter and whiter light output.

Which bulb fits the 1991 Geo Metro fog light?

The 1991 Geo Metro typically does not come with factory fog lights in all trim levels. If your vehicle is equipped with them, check the manual as sizes can vary by trim.

Is the 1991 Geo Metro single or dual beam?

The 1991 Geo Metro uses a dual bulb headlight system. This means you have separate bulbs for high and low beams.

Can I install LED bulbs on my 1991 Geo Metro?

Yes, the 1991 Geo Metro comes with standard halogen bulbs from the factory, but they can be upgraded to LED. You will need a H4666 LED conversion kit for the low beams.

Did the 1991 Geo Metro change headlight bulb sizes from the previous year?

Yes — the 1991 Geo Metro uses different bulb sizes than the 1990 model. The 1991 generation introduced this bulb configuration.

Is the 1991 Geo Metro the first or last year to use H4666 bulbs?

The 1991 Geo Metro is the only year in the 1991 generation to use the H4666 bulb for the low beam headlight.

How do I change the headlight on a 1991 Geo Metro?

Turn off the vehicle and open the hood. Locate the headlight assembly from behind, remove the dust cover or retaining clip, disconnect the wiring harness, twist the old H4666 bulb counter-clockwise to remove it, then insert the new bulb and reassemble. The whole process typically takes 10 to 30 minutes per side depending on accessibility.

Are LED headlights legal for a 1991 Geo Metro?

LED bulbs used off-road or in auxiliary lights are legal everywhere. For on-road headlight use, legality varies by state. Many states allow LED retrofits as long as the beam pattern meets DOT standards. For the best legal compliance, choose a DOT-approved H4666 LED kit that is designed as a direct replacement and produces a proper cutoff pattern without excessive glare.

How much does it cost to replace 1991 Geo Metro headlights?

A pair of halogen H4666 bulbs costs $15 to $40, while LED conversion kits run $25 to $60 per pair. If you have a shop do the work, expect an additional $20 to $50 in labor per bulb. Replacing them yourself at home saves the labor cost and usually takes under 30 minutes.

What is the difference between halogen and LED for a 1991 Geo Metro?

Halogen bulbs produce a warm yellow light (around 3200K), last 500 to 1000 hours, and draw more power. LED bulbs emit a brighter white light (5000-6000K), last 25,000+ hours, and use less energy. LED upgrades for the H4666 position are available as direct plug-and-play replacements.

The 1991 Geo Metro has a unique bulb configuration not shared with adjacent model years.

Fitment Guaranteed for 1991 Geo Metro

What Size Bulbs Does a 1991 Geo Metro Use?

Correct headlight, fog light, and tail light bulb sizes. Sourced from OEM catalog data.

Installation Difficulty

Easy (Plug and Play)

Est. Replacement Cost

$15 - $40 (Halogen) / $30+ (LED)

What Lighting System Does the 1991 Geo Metro Have?

The 1991 Geo Metro utilizes a refined lighting configuration featuring 9 distinct bulb positions. It features a comprehensive lighting system powered by a dual-bulb halogen configuration using separate H4666 low beam and high beam bulbs for precise light distribution. This model belongs to the early years of the Metro's 1989-1997 production span.

Can You Put LED Bulbs in a 1991 Geo Metro?

Upgrading to LED is one of the most effective ways to modernize your Geo's appearance and safety profile. We recommend starting your upgrade with the H4666 low beams, as they see the most use. Adding a matching LED kit later will complete the look and ensure consistent lighting performance.

1991 Geo Metro Bulb Size Chart

Position	Bulb Size	Shop
Side Marker	168	Buy 168 →
Low Beam	H4666	Buy H4666 →
Turn Signal Front	1156	Buy 1156 →
Brake Light	1157	Buy 1157 →
Turn Signal Rear	1157	Buy 1157 →
Tail Light	1157	Buy 1157 →
Reverse Light	1156	Buy 1156 →
Parking Light	194	Buy 194 →
Dome Light	DE3022	Buy DE3022 →

How do the 1991 Geo Metro's bulbs compare to other years?

The 1991 Geo Metro changed bulb sizes from 1990. The previous model year used a different configuration.

The 1992 model switched to a different bulb configuration.

This bulb configuration covers the 1991 model years. ← 1990 1992 →

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Other Metro Years

1997 1996 1995 1994 1993 1992 1990 1989

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