DETROIT -- Maybe it was the brand-new bright red Chevrolet Corvette gleaming in one corner or the elegant BMW coupe in another.Maybe it was just the free-flowing espresso at nearly every stand. But car companies were positively giddy last week as the North American International Auto Show opened in Detroit.They have reason to be.New car and truck sales in the U.S. reached a five-year high of 14.5 million in 2012, and many executives and analysts think they'll climb to 15.5 million this year. Credit is easier to obtain, interest rates are low, and many people who kept old cars during the recession are ready to buy.To catch those customers' eyes at the Detroit show, which opened to the public this weekend, car companies have unveiled 59 new cars and concepts, reflecting what will make its way into showrooms. That's up from just 41 in 2012, a sign that automakers have more profits at their disposal and expect higher sales.Here are five trends at the show:Better mileageOne lesson from the show: There are plenty of ways to squeeze efficiency from cars and trucks.Volkswagen is showing the CrossBlue, a plug-in hybrid SUV prototype that mates a diesel engine with two electric motors. It can travel 14 miles in all-electric mode and gets an estimated 35 miles per gallon while running on both gas and electricity.The Jeep Grand Cherokee is also making a jump to diesel power with an optional 3-liter V-6 diesel that gets 30 mpg on the highway, five better than the gas-powered V-6.Automakers are trying other tricks to save fuel as they face tougher requirements, even in muscle cars. The eight-cylinder engine on the 2014 Corvette kicks down to four cylinders at highway speeds. The grille and wheels of Ford's Atlas concept pickup have shutters that automatically close at high speeds to cut wind drag.Jeremy Anwyl, vice chairman of the Edmunds.com auto website, said many people have been surprised by the resurgence of internal combustion engines as new technology makes them more efficient."It is one reason why we're not all driving hybrids now, or EVs," Anwyl said.Pickups take offWith home construction back on the rise, pickup sales are poised to grow. And Detroit is ready.General Motors is showing its new trucks for the first time at the Detroit show. The Chevrolet Silverado and GMC Sierra, which will go on sale this spring, have mean-looking grilles, restyled interiors, and new engines and transmissions that GM promises will be very efficient.The trucks even have steps inset into the rear bumper so people can jump into the bed to get tools or tie down cargo.Chrysler's just-refurbished Ram pickup -- named "Truck of the Year" by automotive journalists at the show -- is also no slouch, boasting a segment-best 25 mpg on the highway.But Ford, whose F-series has been the top-selling truck for more than three decades, won't cede that title without a fight. The company pulled off one of the show's few surprises, lowering its Atlas pickup concept from the ceiling amid a shower of sparks during media previews.Ford gave few details about the beefy, chiseled Atlas, other than that it hints at the look of the next F-series, due in 2014 or 2015."It sends a message that we hope to continue to strengthen our leadership in commercial vans and trucks," Chief Operating Officer Mark Fields said. "We know there's a lot of people who want to take that away from us."The competition could mean good deals for buyers in a segment already known for discounts.Luxury boomSupple leather seats, finely stitched dashboards and sparkling chrome grilles are everywhere at the show, a sign that car companies are clawing at one another for a piece of the growing and lucrative U.S. luxury market.From a well-crafted new E-class lineup from Mercedes to the decked-out Cadenza luxury sedan from once-lowly Kia, automakers are vying for customers ready to be pampered a little more.Luxury sales grew almost 12 percent last year to over 1 million, and automakers are expecting further increases as people feel better about the economy and the Great Recession recedes into the rearview mirror.For the past few years, much of the U.S. auto sales growth has been in compact and midsize cars at the lower end of the price range, said Jeff Schuster, senior vice president of forecasting for LMC Automotive, a Detroit-area industry-forecasting firm.But recent trends show that buyers who want luxury items such as leather seats and touch screens are coming back to the market and are willing to pay a little more."The premium market took a couple of years off," he said. "I think we're going to see a comeback over the next couple of years."Lincoln continues to revamp its lineup with the MKC concept, a small crossover that is the second of four new Lincolns coming by 2015.Blurring the linesThe unveiling of the BMW 320i sedan, an entry-level 3-series that starts at $33,445, renewed questions about whether luxury cars are starting to bump into mainstream models.In the last couple of years, mass-market brands have started offering features once reserved for luxury brands.Ford offers hands-free automatic parallel parking and lane-departure warning signals on the midsize Fusion. Even the little Dodge Dart has a heated steering wheel.Buyers must decide: Do they buy a loaded Fusion for nearly $37,000 or the new 320i?And carmakers need to decide how to market their cars. The Chrysler 300, for example, competes with other mainstream large cars at the low end, but it has two high-end versions -- the 300c and 300 luxury series -- that compete with BMW."It's really like having two cars," said Olivier Francois, Chrysler's marketing chief. "What we probably need to do is amplify the gap, separate the two poles."Jim Lentz, who runs Toyota's U.S. operations, isn't worried. In his own lineup, he said, the Toyota Avalon and Lexus ES sedans are similar, but few shoppers consider both.Smaller crossoversWith explosive growth in crossover vehicles the past five years, automakers are looking at ways to attract buyers of more efficient SUVs based on car underpinnings.At the Detroit show, Honda opened a new front in the battle with a sharp-looking small SUV.It's based on a subcompact frame and will be smaller than Honda's popular CR-V. This part of the market is attractive to automakers because it lacks well-established competitors."I think the industry as a whole believes there's opportunity here," Schuster said. "It's up for grabs."Nissan is already in the market with its funky Juke. General Motors' Buick is just entering with the Encore.Honda Executive Vice President John Mendel said the new vehicle, called an "urban SUV concept," is designed for city commuters who still want the cargo space, adventurous lifestyle and high sitting position of an SUV.
Five trends at the auto show
A quick look at what to expect when new vehicles arrive in showrooms.