Most 2015 GMC Sierra 2500 models with halogen headlights use H11 for the low beams and 9005 for the high beams. If your truck has HID headlights, the bulbs are typically D1S or D2S with a ballast.
Halogen headlights: standard configuration
The default setup on many 2015 Sierra 2500 pickups is a halogen headlight system. Knowing the exact bulbs helps you source replacements quickly and correctly.
- Low beam bulb: H11
- High beam bulb: 9005 (HB3)
These two bulbs cover the common halogen headlight configuration on most Sierra 2500 models. Always verify with your vehicle’s manual or by inspecting the bulb in the headlight assembly if you’re unsure.
Alternative configurations and upgrades
Some Sierra 2500 trucks may come with upgraded lighting options, including HID headlights. If your vehicle has these, the bulb types differ from halogen and require a ballast system to operate.
- HID headlamps: D1S or D2S bulbs (depending on the ballast installed in your headlight assembly)
Note that HID setups operate with ballast hardware and are not interchangeable with H11/9005 halogen bulbs. If your truck has fog lights, those are often H11 as well, but configurations can vary by trim and factory options.
How to verify and replace bulbs safely
To ensure you purchase the correct bulbs and perform a safe replacement, follow these steps. Always handle bulbs with care and avoid touching the glass with bare skin.
- Check the owner’s manual or the door jamb sticker for the recommended bulb sizes for your exact trim and headlight type.
- Inspect the current bulb in the headlight housing to identify markings (H11, 9005, D1S, D2S, etc.).
- If you see a ballast box near the headlight, your system is likely HID; use D1S or D2S bulbs as indicated by the ballast specifications.
- Purchase OEM or GM-approved bulbs to ensure proper fit and performance; avoid mixing bulb types in the same headlight if possible.
- When replacing HID bulbs, consider whether the ballast or other components also need service, and consult a professional if unsure.
If you’re unsure about your model’s configuration, a quick visit to a trusted auto parts retailer with your VIN or a photo of the headlight assembly can confirm the exact bulb type for you.
Summary
For most 2015 GMC Sierra 2500s with halogen headlights, the bulbs are H11 (low beam) and 9005 (high beam). Some trims or packages use HID headlights, which employ D1S or D2S bulbs with a ballast. Always verify with the manual or a quick inspection of the current bulbs and ballast, and replace with GM-approved components for best results.