[Fixed] Need help: how to unlock a 2021 GMC Sierra 2500HD Denali without the ignition code

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Trying to program a new key - where's the key code on my 2021 GMC Sierra 2500HD Denali?

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

Replies (6)

If this works for my 2021 GMC Sierra 2500HD Denali, I owe you big time.

I tried this with my 2021 GMC Sierra 2500HD Denali but still no luck. Any suggestions?

Thanks! Been struggling with this on my 2021 GMC Sierra 2500HD Denali for a while.

Trying to reprogram a new key for my 2021 GMC Sierra 2500HD Denali—need the code first.

This is gold. I’ve been locked out of my 2021 GMC Sierra 2500HD Denali for days.

Anyone try this on a 2021 GMC Sierra 2500HD Denali with push-button start?

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