At the beginning of the month, diesel prices rose above $3 a gallon for the first time since November 2008. Over the last four weeks, trucking's main fuel has gained 14 cents. This week's average was 87.7 cents higher than the same week last year.
The West Coast saw the highest prices this week at $3.211 a gallon, while the Lower Atlantic region had the lowest, at $3.025 a gallon.
Meanwhile, gasoline prices fell about a penny to a national average of $2.849 a gallon. This was 80 cents above the average during the same week last year.
Crude oil fell below $85 a barrel Monday on fears that the Federal Reserve may raise interest rates, according to reports by Dow Jones. Crude ended trading Monday down 92 cents to $84.20 a barrel on the New York Mercantile Exchange.