

The Difco (formerly Differential Car Co.) is the equivalent of a dump truck.
The low body height makes it easy to load and helps stabilize the car in transit
or while dumping. The car features all-welded steel construction and is built
in various sizes from 50 cubic yards up to 100 tons capacity. The self-contained
dumping system consists of four telescoping air cylinders mounted under the
dump bed. The bed pivots so the load can be dumped on either side of the car.
A single value operates the mechanism. Several cars can be used together with
the dumping being controlled from any car or the locomotive. The bed can rise
to a 50 degree angle and the side door opens automatically. With considerable
accuracy, the entire load can be dumped in under 10 seconds.
Click on the pictures below for a larger view.
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Click here for the Difco dump car's mechanical drawing
2004 Update
In the summer of 2004, the Alaska Railroad found all of their airdump cars were tied up with the Bird Creek project. They were moving 200 carloads of debris a day using two crews from May through August so other projects were suffering from lack of airdumps.. They leased 26 airdumps from the Rick Franklin Corp (RFRX) and now that the season is over and their airdumps are free, they have exported them back to Oregon. Since these cars had a 70 ton capacity (as opposed to 100 tons) the railroad chose not to purchase them.
2007 Update
Notice that the dump car on the left looks newer. Extra-gang foreman Rich Holzapfel says, "We've had those four new 15900 series cars for at least four years. We were able to get them when the Difco company went out of business." Photo taken at Portage, July 2007.
Also see 1928 ad for Western dump cars
© 1998-2008 John Combs unless otherwise noted
Page created 12/3/00 and last updated 9/20/08