After three weeks of increases, the national average retail price of a gallon of diesel fell 0.9 cent to $2.87.
The price, which has climbed 15.3 cents since Dec. 21, is 56.5 cents higher than the same week last year.
Cummins, Daimler North America and Navistar will receive $115 million in fuel efficiency projects.
The national average retail price of a gallon of diesel soared 6.5 cents this week.
Despite the decline, the U.S. average price is 36 cents higher than a year ago.
Some of the regions tracked by the Department of Energy recorded modest price increases.
The national average retail price of a gallon of diesel dropped 1.2 cents to $2.775.
Overdrive's Most Beautiful contest is back for a second year. Submit yourself or a female truck driver you know! The first-place winner will win a trip to The Great American Trucking Show in August and will be featured in a story in Overdrive. Submissions accepted through March 20.
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