Buick LaCrosse 2018 Bulb Size
Bulb size chart
This page covers bulb sizes for the 2018 Buick LaCrosse and helps you verify the correct bulb by lighting position. Whether you are replacing an exterior lamp or an interior bulb, matching the bulb to the exact location is the best way to avoid fitment mistakes.
The 2018 LaCrosse uses a mix of LED lighting and replaceable bulb types depending on the position. Use this guide to identify the right bulb size for headlights, turn signals, reverse lights, license plate lights, cabin lights, and other common lighting points on the car.
Trim level, lighting package, market, and body style can change the bulb used on a 2018 Buick LaCrosse, so always confirm the installed bulb before buying replacements. Some positions are LED assemblies, while others may use halogen-style bulbs or specific replaceable sizes, and aftermarket LED conversions can affect beam pattern, brightness, and warning messages. If you are upgrading from halogen to LED or replacing a previous owner’s modification, compare the old bulb, connector, and housing clearance first to make sure the new bulb fits and functions correctly.
FAQ
What bulb does the 2018 Buick LaCrosse use for the low beam and high beam headlights?
The headlight bulb type listed for both high beam and low beam on the 2018 Buick LaCrosse is D3S.
What is the front fog light bulb size on a 2018 Buick LaCrosse?
Front fog light fitment can vary by version, but the listed options are H11 LED and H16 LED. Check the installed bulb and housing before ordering.
What bulb size is used for the rear turn signal on this car?
The rear turn signal bulb listed for the 2018 Buick LaCrosse is 7440.
What bulb does the brake light use?
The brake light bulb listed for this model is 7440R.
What is the reverse light bulb size?
The back up reverse light bulb listed for the 2018 Buick LaCrosse is 921.
Are the front turn signal, parking light, tail light, and daytime running light bulbs replaceable?
Those positions are listed as LED on this page. In many cases that means the light is part of an LED assembly rather than a simple replaceable bulb, so verify the exact housing before attempting a repair.
What bulb size is used for the license plate lights?
The license plate light bulb options listed are 2825 and 98.
What bulb is used for the trunk or cargo area light?
The trunk or cargo area light uses 194 or 7441, depending on the exact vehicle configuration.
What bulb size fits the dome light, map light, and interior door lights?
The dome light and map light are listed as LED, while the interior door light uses 194 or 7441.
What bulb is used for the stepwell light and vanity mirror light?
The stepwell light uses 194 or 7441, and the vanity mirror light uses 7065.
Do trim levels affect bulb fitment on the 2018 Buick LaCrosse?
Yes. Trim level, lighting package, and market can change the bulb type or whether a light is LED assembly-based, so it is important to match the bulb to the exact vehicle configuration.
Should I check the old bulb before ordering a replacement?
Yes. Checking the installed bulb is the safest way to confirm fitment, especially if the car has been modified, repaired, or fitted with aftermarket LED bulbs.