In 1923-24 UTLX randomly selected aprox forty 6500 gal tanks to be converted for use on the D&RG narrow gauge lines. These cars had their underframes modified for this purpose. These were what we commonly call the Narrow Frame Cars. These were used to move oil from Farmington ove rhe RGS to Montrose. Here the oil was reloaded into standard gauge cars for the trip on to the Salt Lake area. Some of these cars came equipped with heaters (about 25) although the light crude from the Farmington area did not require this. In the 1930's and through the 1940's some of these non heatered cars were used by a number of oil companys to carry gasoline and other refined products.
In 1037, the Colo state highway department required a number of heated cars to move road oil. UTLX then selscted, again at random, 25 Van dyke Tankcars to meet this need. The conversonn of these cars was accomplished by replacing the trucks with narrow gage ones. In 1938 the Gramps field came on line and with the completion of the pipe line to Chama a number of these cars (at least 15) were leased to the Gramps company. The Gramps oil and road oil was thicker and required heated cars. Most of the Narrow frame heater cars were also used in this service .
In 1946, after the war (II), when paving resumed, aprox 20 additional Van Dyke cars were required for the road oil bussuness. These were eqipped with 4'11" whelbase cast steel trucks.