How far can a train move a ton of freight on just one gallon of fuel? 422 miles? Well, that is what they claim

Diesel/Electric CSX train commercial on the radio...

You've probably seen the CSX ad where they ask "What can a car that gets 50 miles on a gallon of fuel do for the environment?" The car then drives up a ramp into a waiting railroad car.
The ad continues "Not nearly as much as the car that's carrying it. Our trains can move one ton of freight 423 miles on one gallon of fuel".
http://www.belowtopsecret.com/forum/thread342169/pg1

Thank you for your inquiry about our advertising.

Our ad states "trains can move a ton of freight 423 miles on a single gallon of fuel," and it is correct. The 423 is calculated by dividing the total tons hauled by a single freight train by the total gallons of fuel used. So, on a per mile, per ton basis, the amount of fuel needed is extremely low. In fact, it is so low that trains are between three and four times more fuel efficient than trucks.
So, even though it takes more than one gallon of fuel to power a train for 423 miles, the train actually uses less fuel than the more than 280 trucks it would take to haul the same amount of freight.
http://timlennoxonline.blogspot.com/2008/11/advertising-claim-by-csx.html

Big discussion about it here: http://discuss.amtraktrains.com/index.php?s=cfca6daeb5eece0b9c0b06e76240342a&showtopic=21592&pid=152083&st=40&#entry152083