I am the original owner of a 2014 GMC Sierra 1500 (VIN: [XXX] ) and began experiencing serious mechanical and electrical issues while the vehicle was still under warranty around 40,000 miles. These included engine RPM fluctuations at idle, vibrations under acceleration above 65 MPH, and intermittent misfiring — all symptoms that are now believed to be early indicators of defective lifters or valve train components. I also experienced repeated electrical failures including a rear turn signal malfunction due to melting/corroded taillight sockets, a thumping rear-end noise, differential knocking, and body panel issues (hood lifting at highway speeds). These were reported multiple times to authorized GMC dealers (Mike Haggerty GMC and Rizza GMC), but I was told there was no issue or no repairs were made. GM refused to assist when I escalated the issue in 2017 via a detailed email, despite all problems occurring within the warranty period. I’m now dealing with a persistent ticking sound from the engine and loss of power, which matches widespread reports of lifter failure in GM’s 5.3L/6.2L V8 engines. These failures pose both a mechanical and safety risk due to stalling, misfiring, and potential electrical fires (in my case, from a failed taillight socket). A class action lawsuit ([XXX], et al. v. General Motors LLC) has been filed regarding these known defects, yet GM has not issued a recall. I’m filing this complaint to add my case to the record and urge NHTSA to investigate these issues. I have full documentation of the original complaint and am willing to provide it upon request. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)