Cadillac CTS 2008 Bulb Size
Bulb size chart
This 2008 Cadillac CTS bulb size page helps you verify the correct bulbs by lighting position, so you can match the right fit before you buy. Whether you are replacing a burned-out headlight, a rear turn signal, or a small interior lamp, checking by location is the easiest way to avoid ordering the wrong part.
The 2008 Cadillac CTS uses a mix of standard halogen bulbs, specialty bulbs, and some LED-equipped positions depending on trim and lighting package. Because fitment can vary by body style and market, this page is meant to help you narrow down the correct bulb size for each exterior and interior light on the vehicle.
For the best fitment results, compare your CTS trim and lighting package against the bulb position on this page before ordering. Some versions use halogen bulbs, while others may have LED assemblies or different headlamp setups, so aftermarket conversions do not always match the original housing or connector. If you are upgrading to LED bulbs, make sure the bulb shape, base, and depth are compatible with the housing, and remember that some retrofit kits may need additional parts or may not be road-legal in every location. When possible, check the installed bulb before purchase, especially for smaller interior lights and any position that can differ by package or market.
FAQ
What bulb size does the 2008 Cadillac CTS use for the low beam headlights?
The listed low beam headlight bulb for the 2008 Cadillac CTS is H11. Some trims may have a different headlamp setup, so confirm the exact headlight type on your vehicle before buying.
What is the high beam bulb size for this CTS?
The standard high beam bulb listed for the 2008 Cadillac CTS is H9. If your car has a different lighting package, check the installed bulb or the headlamp housing to confirm.
Does the 2008 Cadillac CTS use D1S bulbs anywhere?
Yes, a D1S headlight setup is listed for some versions of the 2008 Cadillac CTS under the combined high beam and low beam headlight category. This usually points to a different headlamp configuration than the standard H11/H9 setup.
What bulb does the front fog light use?
The front fog light bulb is listed as H11 LED or H16 LED, depending on the specific setup. Because fog light fitment can vary, it is smart to verify the bulb already installed in the car.
What bulb size is used for the rear turn signal?
The rear turn signal light bulb is listed as LED on this page. Since the rear lighting assembly may vary by trim or market, check the lamp unit before ordering a replacement.
What bulb size is used for the brake lights and tail lights?
Both the brake light bulb and tail light bulb are listed as LED for the 2008 Cadillac CTS. These are typically part of the rear lamp assembly rather than a simple replaceable halogen bulb.
What bulb does the license plate light use?
The license plate light bulb is listed as 2825 or 98. These are common small wedge-style bulbs used in several exterior and interior positions on this vehicle.
What bulb size is used for the parking lights?
The parking light bulb is listed as 2825 or 98. If your CTS has a different front lighting package, confirm the installed bulb before purchasing replacements.
What bulb is used for the front side marker light?
The front side marker light bulb is listed as 194NA. This is a specific fitment note, so it is best to match the bulb code exactly when replacing it.
What bulb does the rear side marker light use?
The rear side marker light bulb is listed as LED. On this model, rear marker lighting may be integrated into the lamp assembly, so replacement can depend on the exact trim and housing.
What are the interior bulb sizes for the dome, map, glove box, and vanity mirror lights?
The dome light bulb is listed as 2825 or 98, the map light bulb is PC175, the glove box light bulb is 906, the interior door light bulb is 906, and the vanity mirror light bulb is 6612F. These small bulbs are often easy to replace once you confirm the exact socket.
What bulb is used for the trunk or cargo area light?
The trunk or cargo area light bulb is listed as 211-2. If the light is dim or intermittent, check the bulb and the socket condition at the same time.
What bulb size is used for the daytime running lights?
The daytime running light bulb is listed as 5201. Because daytime running light setups can vary by market and package, verify the bulb already in the car before ordering.
Can I switch the 2008 Cadillac CTS bulbs to LED?
Yes, some positions can be converted to LED, but fitment depends on the housing, connector, and space available. For example, halogen headlight or fog light replacements may need careful matching to avoid beam pattern issues or installation problems.
Why should I check the installed bulb before buying a replacement?
Checking the installed bulb helps confirm the exact size, base, and housing style, especially on a 2008 Cadillac CTS where trim and lighting package differences can change fitment. It is the safest way to avoid ordering the wrong bulb.