DETROIT, Michigan - General Motors claimed both the Car and Truck of the Year titles but Ford's use of aluminum in its F150 pick-up sparked new debate at the 2014 North American International Auto show in Detroit.IMAGE GALLERY: 2014 Detroit showThe show also saw the debut appearance of Mary Barra as General Motors' new chief executive - the first woman to lead a major automaker. TAKING A RISKBarra, who officially takes the reins of GM on January 16, said: "Our products are the result of putting the customer at the centre of everything we do. "That has fostered a bold new culture at our company, a culture that promotes innovation and encourages risk."Fiat-Chrysler boss Sergio Marchionne pledged to oversee the union of the two brands for at least the next three years and Ford chief executive Alan Mulally is still in his job after finally scotching talk he was headed to Microsoft.Ford executive chairman, Bill Ford, cleared speculation that Mulally could be departing: "Alan has obviously done a great job and I'm thrilled that he's here."Automakers, following a hugely successful 2013, forecast more growth and unveiled powerful new bakkies, sexy sports cars and luxury models.NEW CORVETTES, FORD'S SLIM F150General Motors earned acclaim for its Corvette Stingray and Chevrolet Silverado pick-up. Corvette also generated excitement with racing versions of the Corvette Stingray, the street-legal Z06 and track-tuned CR.7.Chevrolet chief Alan Batey said: "Chevrolet is in the midst of the most aggressive product transformation in its more than 100-year history." Eyes were on Ford, however, as it gambled with a major change for its best-selling F150 pick-up, replacing steel body panels with aluminum to drastically reduce weight and fuel consumption. The move, which helped Ford slash the truck's weight by nearly 320kg was seen as a big risk because bakkie-buyers tend to focus on build-quality and power.SEXY TOYOTA, CHRYSLER'S NEW 200Toyota revved up its design credentials with a provocative new concept sports car - the FT-1, short for Future Toyota 1.Chrysler unveiled its hotly anticipated revamp of its 200 sedan which aims to bring a new level of luxury and styling to its mid-sized offering with a (in the US) low entry price the equivalent of R234 000.Chrysler brand chief Al Gardner said: "We designed the car to take on every other vehicle in its class, feature-by-feature, to prove that a quality sedan doesn't have to cross an ocean to be worthy of an American driveway." Mercedes-Benz dazzled crowds by hiring musician Kelly Rowland to serenade audience while it unveiled the new C-Class sedan. The C-Class moves up from its entry-level sedan status, a role now taken over by the CLA.Also enjoying the move down from senior models is the diminutive Honda Fit (Jazz in SA). Honda has reshaped the front, enlarged the inside with generous legroom for a sub-compact, boosted power to 97kW and worked to smooth the ride and added, Bluetooth, rear-view cameras and upgraded smart phone connectivity.Kia launched its new GT4 Stinger sports car while BMW served up a hat trick of new models (2 Series, M3 and M4).FIAT-CHRYSLER ISSUESExecutive leadership issues were also settled at Fiat, two weeks after the company bought the remaining 41.5% of Chrysler that it didn't own after long, tough negotiations. Chairman John Elkann said CEO Sergio Marchionne will remain until at least 2017.With the completion of the takeover of Chrysler - now the main money-maker for the Italian group - Marchionne said the Fiat board would soon meet to discuss integration, including possibly moving the conglomerate's HQ to Detroit and listing its shares on a major stock market.