General Motors on Friday further expanded customer incentives, offering six-year loans at a rate of 1.9% on most vehicles to boost sluggish US sales, Reuters said, adding that the new incentives come on top of GM's zero-percent financing offer on five-year loans on most cars and trucks announced earlier this month. Up to now, GM had only offered six-year loans on a few models, like the Chevrolet Cavalier and Pontiac Sunfire small cars, and the Chevrolet S-10 and GMC Sonoma compact pickup trucks, the news agency said.