High-profit pickups and SUVs aren't selling well, so how is an auto maker supposed to bolster the bottom line without a product pipeline overflowing with fresh new vehicles?

Several OEMs are facing this quandary at the moment, including Nissan Motor Co. Ltd. The Japanese auto maker's strategy is to declare 2010 the year of the sedan and to relaunch its 4-door models, the Maxima, Altima, Sentra and Versa.

Nissan is using the term “relaunch” not to suggest anything was wrong when the latest-generation vehicles arrived in the market (Maxima in 2008, the other three in 2006) but to highlight new features added this year.

To appreciate Nissan's desire to embrace sedans, consider the latest sales figures for the Titan pickup. In 2009, the auto maker delivered an abysmal 19,042 Titans, down 44% from 2008.

The Titan was outsold more than 4-to-1 by the Toyota Tundra. For perspective, the Tundra lagged the Ford F-Series pickup 5-to-1.

Nissan has sold more cars than trucks the past two years in a mix soon headed for a 60/40 split, Mark Perry, director-product planning and advanced technology strategy for Nissan North America Inc. tells Ward's.

Prior to that, Nissan consistently sold more trucks than cars. “For sure, people are going to smaller vehicles because of miles-per-gallon and household incomes,” Perry says.

Revisions to the sedans are not extensive from a mechanical standpoint.

The engines and transmissions are the same, as are suspensions and steering systems, so handling and maneuverability are unchanged. Electronic stability control (branded by Nissan as VDC) now is standard on all four sedans, except the base Versa. The feature is optional on that model, which stickers for under $10,000.

Most of the enhancements are cosmetic in nature, consisting of new grilles and exterior colors, larger display screens and improved connectivity for MP3 players.

On the safety front, there are no head restraints for the middle backseat occupant. Perry says the earlier models did not offer them either. Some competitive vehicles, however, do offer three restraints in the back seat.

The biggest upgrade in the flagship Maxima is the 6.5-in. (16-cm) color monitor for the navigation and rearview camera system. The new screen is easier to read than the 4.3-in. (11-cm) unit it replaces.

Also offered on the Maxima are two new exterior colors (crimson black and ocean gray), a 2GB music server, new wheel finishes, Bluetooth streaming audio and XM NavWeather, which alerts the driver to bad weather ahead. A link for Bluetooth-enabled phones is standard.

The fourth-generation Altima continues to be offered as a sedan, coupe and hybrid and remains Nissan's best-selling vehicle. It offers a restyled hood, grille and front bumper and new 16-in. and 17-in. alloy wheels.

Inside, the Altima offers improved fabrics and finishes, revised gauges and a USB port with MP3 connectivity. Like the Maxima, the Altima gets the next-generation nav system with the larger 6.5-in. screen and available XM NavWeather and Bluetooth streaming audio.

Both the 4-door Altima and Maxima come standard with a continuously variable transmission, but the Altima coupe is available with a 6-speed manual. Altima pricing is up an average $300. The manual transmission in the Altima sedan no longer is offered.

The Sentra sedan is repositioned to attract both cost-conscious buyers as well as customers seeking more luxurious features in a small car. For instance, leather-appointed seats now are available as a package, and optional content includes navigation, a rearview camera and premium audio.

Sentra prices have dropped between $600 for a $17,160 2.0S model and $1,080 for a $19,580 SE-R sport.

The Sentra also gets revised headlights and taillights, a new grille and front fascia, standard VDC, updated wheels and new interior fabrics.

For the Versa sedan and 5-door hatchback, new features include the front grille and 16-in. alloy wheels and 15-in. (38-cm) wheel covers.

Inside, the Versa offers new wood-grain trim, instrument clusters, seat and trim fabric, audio lineup and optional sport interior. Although upgraded, the Versa interior remains bathed in hard plastic.

The Versa might be the smallest Nissan sedan, but its sales numbers are significant. In Ward's Lower Small car segment, the Versa has led the way, outselling the Toyota Yaris, Chevrolet Aveo and Hyundai Accent.

The Altima continues to hold its No.3 spot in the fiercely competitive Upper Middle car segment, despite a 24% sales decline in 2009.

The Altima trails only the Honda Accord and Toyota Camry, while outselling formidable rivals such as the Chevrolet Impala and Malibu and Toyota Prius.

The Maxima remains a strong entry in the Large Car segment, trailing only the Dodge Charger. Maxima sales were up a surprising 13% in 2009, outselling the Chrysler 300, Toyota Avalon and older Ford Taurus.

Meanwhile, in 2009, the Sentra lagged well behind the Ford Focus, Hyundai Elantra, Chevrolet Cobalt, Honda Civic, Mazda3, Toyota Corolla and Volkswagen Jetta.