PI 2024–2026 Sierra 1500/Sierra 2500HD/Sierra 3500HD/Yukon/Yukon XL Service Column Lock Message and DTC U3000 — PIT6549

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Preliminary information · Preliminary information PIT6549

This is a preliminary information note, not a recall. GMC sends these to dealer technicians about a known condition, often while a fix is still being worked out. They are not repair orders, and they don't by themselves change what is covered.

Published: Sep 21, 2026
Applies to: Sierra 1500: 2024–2026 · Sierra 2500HD: 2024–2026 · Sierra 3500HD: 2024–2026 · Yukon: 2025–2026 · Yukon XL: 2025–2026

Summary (official text)​

This preliminary information communicates an issue with a service column lock message and DTC U3000. Engineering is working on the issue and in the meantime dealerships are to reset/clear the DTC and perform four sleep cycles to verify the DTC does not return.

Sources​

• PIT6549 (PDF, NHTSA document 11037551) — Sep 21, 2026

Details from NHTSA as of Oct 22, 2026. If NHTSA or GMC revises this notice, this post is updated and significant changes are noted in a reply. The linked documents are the authority, and a dealer can confirm whether it applies to your VIN.

Have you experienced this issue with your vehicle? Let us know your model year and engine, plus any diagnosis or repair details.

 

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