DETROIT -- America is getting back to work, and it needs pickups.Strong truck demand in March drove U.S. auto sales to their highest monthly total since August 2007, as everyone from oil and gas producers to home builders raced to replace their aging trucks. Overall auto sales rose 3.4 percent from March of last year."I think day-to-day business is the best it's been in five years," said Tim Parker, owner of a Chrysler-Dodge-Jeep-Ram dealer in Hot Springs, Ark. Parker recently joined a Chrysler program that helps him stock pickups so he has inventory ready for business owners.March is typically a good month for the auto industry. Many car buyers put their tax refunds checks toward a down payment. And Japanese automakers, whose fiscal year ends in March, often juice sales with big incentives to end the year on a high note.But this year had additional incentives for buyers. Fuel prices ended the month lower than a year ago. The number of Americans seeking unemployment benefits fell to a five-year low in March. Interest rates are low. And the stock market -- which is a strong predictor of auto sales -- closed the first quarter with the S&P 500 at an all-time high.New cars are also enticing buyers. The redesigned Nissan Altima sedan outsold the Toyota Camry, the perennial midsize king, in March by 100 vehicles. That hadn't happened since May 2011. The redesigned Honda Accord, which went on sale at the end of last year, also came close to outselling the Camry.But pickups were the big drivers. GM, Ford and Chrysler sold a total of 154,722 full-size pickups, up 14 percent from a year ago. It would be the third straight month that pickup sales have outpaced overall industry sales.1.45 million soldTotal sales in March reached 1.45 million, the highest monthly total since August 2007, according to AutoData.Sales at Ford and GM each rose around 6 percent in March. GM reported big increases for Buick and Cadillac, which both have new small cars, while Ford's Fusion sedan and Escape SUV both had record monthly sales. Ford's Lincoln luxury brand was down 23 percent. But the arrival of the MKZ sedan at dealerships this month should help turn sales around, the company said.Toyota said its sales were up 1 percent. Sales of the new Toyota Avalon and Lexus ES sedans doubled over last March, making up for double-digit losses for the Prius hybrid and Camry sedan.Chrysler's sales rose 5 percent thanks to a 25 percent increase for the Ram pickup and big gains for the Dodge Avenger and Challenger sedans.