The 6.6-liter Duramax also continued to be backed by the 6-speed Allison 1000 automatic. The GMC Sierra 2500HD/3500HD were the first "heavy-duty" trucks to offer an Adaptive Cruise Control (ACC), a Forward Collision Warning System (FCWS), and a Lane Departure Warning System (LDWS) available together as part of the available Driver Assist Package. The Driver Assist Package was standard equipment on the GMC Sierra 2500HD/3500HD Denali, and optional on most other Chevrolet Silverado 2500HD/3500HD and GMC Sierra 2500HD/3500HD models. Other new options for the Silverado and Sierra 2500HD/3500HD models included an eight-inch, full-color, reconfigurable LCD Driver Information Center (DIC) screen (for Sierra 2500HD/3500HD Denali models only), a 110-Volt AC household-style power outlet, up to six available USB ports, an available eight-inch touchscreen infotainment system, and a power-sliding rear window with integrated defroster. In mid-year 2015, Chevrolet and GMC made enhancements to the all-new Silverado 2500HD/3500HD and Sierra 2500HD/3500HD. Some of these enhancements included a new OnStar telematics system with 4G LTE Wi-Fi capabilities, new wheel designs, new exterior paint color options, new exterior tow mirror designs, a USB port added the glove compartment of trucks equipped with a front bench seat, DURALIFE brake rotors, the availability of dual 150 and 220 amp alternators for models equipped with the 6.6-liter Duramax Turbodiesel V8 engine, an off-road information screen added to the instrument cluster of 4X4 models equipped with the Z71 or All-Terrain Packages (the latter is a GMC-only option), a Bi-Fi Compressed Natural Gas (CNG) option for models equipped with the 6.0L Vortec gasoline V8 engine, a new All-Terrain Package available on SLE and SLT Double Cab and Crew Cab models (for GMC models only), a standard heavy-duty locking rear axle for all models, and the removal of HD Radio from the "up-level" IO5 and IO6 infotainment systems. A Regular Production Option (RPO) Code of "AVF" in the upper glove compartment distinguishes early-build 2015 models from their 2015.5 successors. Special Editions For 2015, Chevrolet introduced Special Edition for the Silverado truck series. They are in the following series of Rally Edition 1 and 2, Midnight Edition, Custom Sport Edition, Custom Sport Plus Edition, Black Out Edition, and Texas Edition. 2016 facelift For 2016, the Chevrolet Silverado 1500 and GMC Sierra 1500 received its first mid-cycle refresh, similar to 2003 first generation models. The refreshed Silverado and Sierra received a new grille, new headlights and new front fascia, with design influences from