General Motors is now offering special interest-free financing on its U.S. models to commercial-vehicle customers. The program, an expansion of its recently announced retail incentive, will expire Oct. 31. GM noted that as an alternative, current customer-cash and special-fleet incentives remain in effect.

However, the incentive program excludes medium-duty trucks.

GM says the overall program, dubbed “Keep America Rolling,” is intended to help boost the U.S. economy out of its current slump.

“As the largest automaker in the U.S., GM has a responsibility to help stimulate the economy and keep American businesses working,” said David A. Hansen, gm of GM Fleet & Commercial Operations. “We also want to support our dealers and suppliers, and to keep our plants operating and our employees working.”