CHARLESTON — It’s a variation of cash for clunkers.

The South Carolina State Ports Authority announces a program Thursday where truckers serving the Port of Charleston get $5,000 if they upgrade their rides.

Those with trucks built before 1994 get the money if they scrap and replace their trucks with 2004 or newer models. The idea is that newer trucks use less fuel and release less pollution.

It’s part of continuing efforts by the Ports Authority to improve air quality.

Last year, the agency, working with the federal government and private companies, completed a $3.5 million effort to install cleaner engines on container-lifting equipment, two tugs, a dredge and 40 trucks.

That project should eliminate 2,000 tons of air emissions during the life of the equipment.