[Update] How can I access my 2020 GMC Sierra 3500 HD's key code to program new keys?

3863 views - Last reply: March 18, 2025
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How to get my 2020 GMC Sierra 3500 HD's key code to program replacement keys?

Hello! We've developed a VIN-based tool to help you get your key code for the 2020 GMC Sierra 3500 HD. Check it out here: VIN Key Code Generator.

Replies (5)

I’m in the same boat with my 2020 GMC Sierra 3500 HD. This looks promising.

My 2020 GMC Sierra 3500 HD's been in the garage for a week over this. Thanks!

Just tried this on my 2020 GMC Sierra 3500 HD—anyone else have success?

Will this work for older 2020 GMC Sierra 3500 HDs? Mine's a 2009.

My 2020 GMC Sierra 3500 HD just sits silent—hoping this changes that.

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