The Acura MDX, or Honda MDX as known in Japan and Australia, is a mid-size three-row luxury crossover, produced by the Japanese automaker Honda under its Acura luxury nameplate since 2000. The alphanumeric moniker stands for "Multi-Dimensional luxury". According to Honda, the MDX is the best-selling three-row luxury crossover of all time. It has ranked as the second-best selling luxury crossover after the Lexus RX, which offers only two rows of seats. The 2014 MDX Prototype was unveiled at the 2013 North American International Auto Show, the production version was revealed at the New York Auto Show. Production began on May 2, 2013. The MDX is now powered by a 3.5-liter direct injected Earth Dreams V6 with Variable Cylinder Management. A front-wheel drive (FWD) model is available for the first time in the United States, but not in Canada, where all-wheel drive is the only configuration offered. EPA-estimated fuel economy is improved with all-wheel drive (SH-AWD) models rated at 18/27/21 mpg (city/highway/combined) and FWD models rated at 20/28/23 mpg. The interior reduced button clutter by adding a 7-inch touchscreen with haptic feedback, an additional 8-inch screen is also standard. To reduce interior noise an acoustic (PVB layered) windshield, acoustic front door glass and thicker rear glass are used as well as triple sealed door openings. Advance package models include further noise reduction using a thicker carpet base layer and front fender liners. The seating H-point has been reduced and the steering gear ratio is 9% quicker for a more sporty feel. The MDX rides lower reducing its center of gravity. According to Acura, the exterior is more aerodynamic reducing drag by 16% with the new model lapping Nurburgring 8 seconds faster than its predecessor. The headlights are Acura's Jewel Eye LED Headlights. Each headlamp uses five separate LED sources with three used for low-beam lighting and two for high-beam lighting. LED bumper mounted fog lamps are offered as a dealer installed option. Structure rigidity is improved and weight reduced through increased use of high-strength steel. Overall, 64% of the total vehicle body mass is high strength steel, aluminum and magnesium. In terms of safety, the MDX adds a standard driver's knee airbag, optional Lane Keeping Assist System and Collision Mitigation Braking System. The Adaptive Cruise Control now comes with stop and go functionality.