2021 GMC Sierra 2500HD Headlight Bulb Size
By clicking the link you will be redirected to Amazon. The aftermarket bulbs & headlights below may improve the illumination of your vehicle and make it stand out from the crowd.
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Headlight Bulb High Beam and Low Beam - D5S
Center High Mount Stop Light Bulb - 921
Turn Signal Light Bulb Front - 7443
License Plate Light Bulb - 2825
Parking Light Bulb - 7443
Tail Light Bulb - 7443
Turn Signal Light Bulb Rear - 7443
Side Marker Light Bulb Rear - 194
Back Up Light Bulb - 921
Trunk or Cargo Area Light - 921
The 2021 GMC Sierra 2500HD bulb size chart specifies the recommended lamp part numbers and types for all positions of its electrical system, like headlights, fog lights, brake lights, side markers, etc. If you want to upgrade the headlights, the aftermarket bulb you select has to be the exact size your 2021 GMC Sierra 2500HD requires to fit into the housing and match the wattage and voltage specifications. Pay special attention to the marking and make sure the bulb is “DOT” compliant to avoid legal issues.