Sales of commercial and government fleet vehicles from eight manufacturers started 2015 with nearly double-digit gains as major manufacturers such as Ford and General Motors continued shifting car sales away from rental fleets, according to Automotive Fleet data.

For the month, sales to commercial fleets increased 9.1% to 46,972, and sales to government fleets increased 32.1% to 14,426 vehicles.

Commercial sales of trucks, vans, and SUVs increased 8.9% to 39,663 from a year ago, while sales of cars increased 10% to 7,309 units. Government truck sales increased 23.6% to 11,971, while car sales increased 73.6% to 2,455.

Meanwhile, sales of passenger cars to rental fleets fell 11% to 85,835. Truck sales to rental fleets increased 59.1% to 46,144. Overall rental sales rose 13.5% to 131,979 units.

General Motors and Ford reported increased commercial fleet sales in their January sales reports. GM grew commercial sales by 6% in January and has increased commercial sales 38% since 2013, according to the company. At the same time, GM reduced rental deliveries by 13,000 compared to January of 2015.

"GM expects another significant reduction in rental deliveries in 2016," the company said in a release.

General Motors increased fleet and retail sales of its Chevrolet Silverado and GMC Sierra trucks by 7% in January.

Ford continues to see strong commercial demand for its F-150 and Transit van. Ford sold 9,631 Transit vans in January, which represents a 51% increase from January of 2014. Total vans sales rose 20% for Ford.

Ford sold 51,540 F-Series vehicles to retail and fleet customers, which was down 5% from a year ago. The average transaction price increased $2,500 and incentive spending fell $500.

"We continue seeing strong commercial fleet orders for F-150 and will be filling more orders this year," said Mark LaNeve, vice president of U.S. marketing, sales and service. "As the largest seller of commercial vehicles, this represents good news for Ford trucks and the overall economy."

FCA US doesn't separate fleet and retail sales in its numbers, but reported a 5% increase in January in its Ram Truck brand that supplies fleets with trucks and vans. Sales of Ram pickups increased 5% and the Ram ProMaster and ProMaster City vans "each logged their best January sales ever," according to a release.