What is the low beam headlight bulb size for a 2018 Cadillac CT6?

The 2018 Cadillac CT6 uses a LED Headlights bulb for the low beam headlights. We recommend upgrading to LED for better visibility.

What is the high beam headlight bulb size for a 2018 Cadillac CT6?

The high beam bulb size for the 2018 Cadillac CT6 is LED Headlights.

Why are my 2018 Cadillac CT6 headlights dim?

Dim headlights on a 2018 Cadillac CT6 can be caused by aging halogen bulbs, which lose brightness over time, or oxidation (cloudiness) on the plastic headlight lenses. Upgrading to a LED Headlights LED conversion kit can provide a significantly brighter and whiter light output.

Which bulb fits the 2018 Cadillac CT6 fog light?

The 2018 Cadillac CT6 uses a LED Fog Light bulb for the fog light position.

Is the 2018 Cadillac CT6 single or dual beam?

The 2018 Cadillac CT6 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 2018 Cadillac CT6?

Yes, the 2018 Cadillac CT6 comes with standard halogen bulbs from the factory, but they can be upgraded to LED. You will need a LED Headlights LED conversion kit for the low beams.

Does the 2018 Cadillac CT6 have fog lights?

Yes, the 2018 Cadillac CT6 takes a LED Fog Light bulb for the fog light position.

How do I change the headlight on a 2018 Cadillac CT6?

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 LED Headlights 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 2018 Cadillac CT6?

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 LED Headlights 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 2018 Cadillac CT6 headlights?

A pair of halogen LED Headlights 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 2018 Cadillac CT6?

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 LED Headlights position are available as direct plug-and-play replacements.

This vehicle is part of the 2016–2018 Cadillac CT6 generation. All models in this range share identical light bulb sizes.

Fitment Guaranteed for 2018 Cadillac CT6

What Size Bulbs Does a 2018 Cadillac CT6 Use?

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

Installation Difficulty

Moderate (Dust covers often present)

Est. Replacement Cost

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

What Lighting System Does the 2018 Cadillac CT6 Have?

When it comes to nighttime visibility, the 2018 Cadillac CT6 relies on an arrangement of 11 specialized bulbs. It features an extensive lighting system powered by factory-integrated LED technology, which offers superior longevity and a modern cool-white appearance compared to traditional bulbs. This model belongs to the late years of the CT6's 2016-2018 production span.

Can You Put LED Bulbs in a 2018 Cadillac CT6?

Upgrading to LED is one of the most effective ways to modernize your Cadillac's appearance and safety profile. Since your CT6 uses a single LED Headlights 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 LED Fog Light fog lights; switching these to LED can dramatically improve your visibility in adverse weather.

2018 Cadillac CT6 Bulb Size Chart

Position	Bulb Size	Shop
Low Beam	LED Headlights	Buy LED Headlights →
High Beam	LED Headlights	Buy LED Headlights →
Fog Light	LED Fog Light	Buy LED Fog Light →
Brake Light	LED Bulb	Buy LED Bulb →
Side Marker	LED Bulb	Buy LED Bulb →
Turn Signal Front	LED Bulb	Buy LED Bulb →
Turn Signal Rear	LED Bulb	Buy LED Bulb →
License Plate	LED Bulb	Buy LED Bulb →
Parking Light	LED Bulb	Buy LED Bulb →
Reverse Light	921	Buy 921 →
Trunk Light	175	Buy 175 →

Installation Guide

Open in YouTube →

Video suggestion: Installation GuideBy YouTube

Other CT6 Years

2017 2016

More from Cadillac

ATS Allante Brougham CTS Catera DTS DeVille Deville