BorgWarner is a Tier I auto-parts supplier that has two operating segments. The engine group makes turbochargers, emissions system components, timing chains, and other items that enhance fuel efficiency and reduce emissions. Engine group products have averaged about 70% of sales. Drivetrain group produces transmission and four-wheel-drive/all-wheel-drive system components that facilitate the distribution of engine torque to the wheels. Wet dual-clutch products enable more fuel-efficient automotive transmissions.