More likely, however, is the return of the 4.5L “LMK” Duramax turbodiesel V-8, which was due for the 2010 model year before being scrapped. Back then, rumors insisted the engine would produce 310 hp and 520 lb-ft, numbers that would absolutely shame both the Ford 3.0L Power Stroke and the Ram 3.0L EcoDiesel. In fact, the LMK would come close to matching the larger, heavier Nissan Titan XD’s 5.0L Cummins V-8, making us wonder if General Motors might be considering reviving the “1500HD” designation for certain configurations of the 2019 Chevy Silverado and GMC Sierra.