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  • LED Sidemarkers for 20-21 Sierra 2500/3500 HD Set Diode Dynamics (Set Of Four)Smoked
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Diode Dynamics

GMC Sierra HD (20-21): LED Sidemarkers

SKU: DD5127

Regular price $219.50
Regular price $219.95 Sale price $219.50
Shipping calculated at checkout.

BACKORDER: 8-12 Week

What's Included

Tech Specs




Upgraded Styling. These LED sidemarkers are a plug-and-play replacement for the factory fender lights, illuminating the entire width of the housing for a distinctive look and brighter appearance.

Unique Startup. Both the standard and sequential models feature a unique startup sequence. Every time the sidemarkers turn on, they illuminate in an intense amber color starting from the center then spreading to either side. Once they are completely illuminated, they gradually return to a running light mode.

Sequencing Turn Signal. Our sequential option provides an upgrade in functionality. Anytime you hit your turn signal, the sidemarkers illuminate in a sequencing amber pattern to indicate signaling! The sequential option uses the included plug-and-play harness to power the fender lights using the headlight connector.


  • Sidemarkers illuminate in bright amber color
  • Lens Color Smoked
  • Smoked: A dark, smoked-out appearance that blends nicely with the factory fender. (May not meet compliance requirements in your region.)


  • Plug-and-play compatible with GMC Sierra HD 2020+ fender lights
  • Dynamic startup sequence with animated effect
  • Fully-illuminated housing, with dual-lens design for an even glow
  • Optional Sequential turn signal feature, with plug-and-play wiring harness
  • OEM-grade construction and perfect fitment
  • Engineered and assembled in USA