[Fixed] Can someone explain which code I need for 2021 GMC Sierra 2500 HD key?

446 views - Last reply: January 29, 2025
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How do I find the key code to program a key for my 2021 GMC Sierra 2500 HD?

Hello! We've developed a VIN-based tool to help you get your key code for the 2021 GMC Sierra 2500 HD. Check it out here: VIN Key Code Generator.

Replies (6)

Following closely—this could be the fix I need for my 2021 GMC Sierra 2500 HD.

Appreciate any advice—my 2021 GMC Sierra 2500 HD won’t recognize the key.

Will this work if the 2021 GMC Sierra 2500 HD has an aftermarket alarm?

Desperate to get my 2021 GMC Sierra 2500 HD running again. Trying this tonight.

Thanks for sharing! Been looking for a key code fix for my 2021 GMC Sierra 2500 HD.

Can confirm it worked for my 2013 2021 GMC Sierra 2500 HD.

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