What is the low beam headlight bulb size for a 1986 Cadillac Seville?

The 1986 Cadillac Seville uses a 9004 bulb for the low beam headlights. We recommend upgrading to LED for better visibility.

What is the high beam headlight bulb size for a 1986 Cadillac Seville?

The high beam bulb size for the 1986 Cadillac Seville is 9004.

Why are my 1986 Cadillac Seville headlights dim?

Dim headlights on a 1986 Cadillac Seville can be caused by aging halogen bulbs, which lose brightness over time, or oxidation (cloudiness) on the plastic headlight lenses. Upgrading to a 9004 LED conversion kit can provide a significantly brighter and whiter light output.

Which bulb fits the 1986 Cadillac Seville fog light?

The 1986 Cadillac Seville uses a 881 bulb for the fog light position.

Is the 1986 Cadillac Seville single or dual beam?

The 1986 Cadillac Seville uses a single bulb (dual filament) headlight system. This means one bulb controls both high and low beams.

Can I install LED bulbs on my 1986 Cadillac Seville?

Yes, the 1986 Cadillac Seville comes with standard halogen bulbs from the factory, but they can be upgraded to LED. You will need a 9004 LED conversion kit for the low beams.

Does the 1986 Cadillac Seville have fog lights?

Yes, the 1986 Cadillac Seville takes a 881 bulb for the fog light position.

Did the 1986 Cadillac Seville change headlight bulb sizes from the previous year?

Yes — the 1986 Cadillac Seville uses different bulb sizes than the 1985 model. The 1986–1988 generation introduced this bulb configuration.

Is the 1986 Cadillac Seville the first or last year to use 9004 bulbs?

The 1986 Cadillac Seville is the first year in the 1986–1988 generation to use the 9004 bulb for the low beam headlight.

How do I change the headlight on a 1986 Cadillac Seville?

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 9004 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 1986 Cadillac Seville?

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 9004 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 1986 Cadillac Seville headlights?

A pair of halogen 9004 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 1986 Cadillac Seville?

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 9004 position are available as direct plug-and-play replacements.

The 1986 Cadillac Seville is the first model year to use this bulb configuration (1986–1988).

Fitment Guaranteed for 1986 Cadillac Seville

What Size Bulbs Does a 1986 Cadillac Seville 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 1986 Cadillac Seville Have?

When it comes to nighttime visibility, the 1986 Cadillac Seville relies on an arrangement of 9 specialized bulbs. It features a comprehensive lighting system powered by a halogen-based setup where a single 9004 dual-filament bulb handles both low and high beam duties within the same reflector. This model belongs to the mid years of the Seville's 1976-2004 production span.

Can You Put LED Bulbs in a 1986 Cadillac Seville?

Upgrading to LED is one of the most effective ways to modernize your Cadillac's appearance and safety profile. Since your Seville uses a single 9004 bulb for both high and low beams, ensure your chosen LED kit is "dual-beam" compatible. This allows the LED circuitry to mimic the two-filament design of the original halogen bulb. Don't forget the 881 fog lights; switching these to LED can dramatically improve your visibility in adverse weather.

1986 Cadillac Seville Bulb Size Chart

Position	Bulb Size	Shop
Fog Light	881	Buy 881 →
High Beam	9004	Buy 9004 →
Low Beam	9004	Buy 9004 →
Parking Light	194	Buy 194 →
Side Marker	194	Buy 194 →
Reverse Light	1156	Buy 1156 →
Brake Light	1156	Buy 1156 →
License Plate	194	Buy 194 →
Dome Light	912	Buy 912 →

How do the 1986 Cadillac Seville's bulbs compare to other years?

The 1986 Cadillac Seville changed bulb sizes from 1985. The previous model year used a different configuration.

The 1987 model continues with the same bulb sizes.

This bulb configuration covers the 1986–1988 model years. ← 1985 1987 →

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Other Seville Years

2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 1993 1990 1989 1988 1987 1985 1984 1983 1982 1981 1980 1979 1978 1977 1976

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