When the California Air Resources Board ordered that diesel trucks install filters to reduce emissions in 2007, it gave truckers three years to find up to $21,000 and upgrade their trucks. In addition, the board set up a $22 million fund to help truckers with the expense. But starting tomorrow, that deadline expires, and some 1,200 independent truckers will be banned from hauling freight to and from the Port of Oakland. According to the Oakland Tribune, a number of these truckers have sued to overturn the ban, alleging that the grant program was confusing and may have hurt their chances to retrofit their trucks. The plaintiffs are also asking the court to let their unfiltered trucks operate while the case is being resolved.