On July 1, twelve states increased the tax rate on diesel. The largest rate hikes were in Ohio and Illinois. This region has some pretty heavy truck traffic which would lead to larger fuel bills for trucking companies. The smaller carriers are getting hit harder then the larger ones because they have less fueling options in their area and less leverage with fuel providers.
States use these extra taxes to build and maintain all that is involved with their transportation infrastructure. As these can be a necessary thing, large fuel jumps need to be managed differently by small carriers and owner operators.