NHTSA Complaint #11717695 — 2024 GMC YUKON XL

****This complaint is an addendum to ODI Complaint #11715415 **** This report updates the prior complaint to reflect complete engine seizure and pending engine replacement following post-repair loss of propulsion. I respectfully request that NHTSA include my vehicle’s failure in its ongoing evaluations related to L87 engine failures, including Recall 25V-274, Engineering Analysis EA25007, and Recall Query RQ26001. My 2024 GMC Yukon XL Denali experienced progressive internal engine failure beginning at approximately 61, 975 miles. First attempt: The vehicle required camshaft and lifter replacement due to internal mechanical damage. Immediately after 4.5 week repair, the vehicle suffered sudden loss of motive power at highway speed.  The engine shut down without warning at 75 mph with children in the car. (Car was in owners possession for no more than 15 hours, and was driven 25 miles on the highway when it switched to neutral and shut down). Second attempt: The vehicle was towed back to the dealership. Additional electrical repairs were then attempted. (Fuse box) It shut down again during dealer testing. Third attempt: Subsequent internal inspection revealed cylinders 5 and 6 seized, requiring full engine replacement. This represents: • Repeated loss of motive power • Escalation from top-end failure to catastrophic lower-end seizure • Failure occurring immediately after dealer-performed repair(s) • A 2024 model-year vehicle with relatively low mileage Given NHTSA’s ongoing investigations into post-remedy failures (RQ26001) and out-of-scope bearing failures (EA25007), I request that this incident be evaluated as part of the broader defect pattern analysis.