Extensive tank car research was done by Steve Swanson. When Blackstone did their cars in HOn3 Steve wrote the short history.
In 1924, as the standard gauge Farmington Branch of the Denver & Rio Grande Western Railroad was converted to narrow gauge, the Union Tank Car Co. was rebuilding 25 standard gauge framed 6,000-6,500 gallon tank cars to narrow gauge specifications at their Lima, Ohio shops. The tanks, frames, and 4-foot 8-inch arch bar trucks were shipped to Alamosa, Colorado for final assembly by the D&RGW carmen in August, 1924. These UTLX cars retained their original road numbers. All cars carrying the UTLX reporting marks were leased from the Union Tank Car Company, and were not owned by the carrier railroad.
These narrow frame cars were put into service and headed west from Alamosa to handle shipments of Farmington, New Mexico crude oil. The shipments would route to Durango, Colorado for transfer to the Rio Grande Southern and a trip north to Ridgway, where they would again transfer to the D&RGW trackage bound for Montrose. There, the crude was transferred into standard gauge tank cars for eventual delivery to the Midwest Oil and Refining plant in Salt Lake City. The empties would then head back to Farmington for reloading. In April, 1929, a landslide occurred on the RGS railroad interrupting traffic and the Farmington crude would hereafter route east out of Durango on a circuitous run to the Utah refinery.
The completion of the Farmington Conoco refinery in 1925 encouraged UTLX to construct 15 more narrow frame 6,500 gallon tank cars at their Whiting, Indiana shops in February, 1927. The most obvious feature that distinguishes the 1924 cars from the 1927 group are the oblong holes decorating the second-hand side frames of the latter group. It appears that the 1927 tanks included heater pipes inside the tank. These were attached to an external steam source which would heat the contents and expedite the unloading of the heavy petroleum product. Like their 1924 sister cars, these were assembled in Alamosa by the D&RGW. All of these cars had type “E” heaters except for the 12904, which had a type “L” heater. In the mid 1930s, UTLX sold seven of the “No Heater” tank cars, with one car going to the Sumpter Valley Railway and six others to the Penn-Conley Tank Corporation, carrying new reporting marks as CYCX 60-65 and continuing service on the Colorado and New Mexico narrow gauge shipping Texaco gasoline.
Sometime during World War II, twelve of the narrow frame “No Heater” cars and five others being used in Road Oil Service received dome platforms and ladders.
Between March and April 1947, the 34 narrow frame tank cars assigned to the narrow gauge were renumbered in the 88000 series according to the type of heater installed. These cars were again renumbered in the 11000-11033 series in February 1956. On February 7, 1958, the D&RGW purchased two narrow frame “No Heater” cars (11007 and 11008) for use as auxiliary water cars with Rotary Snow Plows OM and OY.
By 1962, 16 of the narrow framed heater equipped cars were sold to the White Pass and Yukon. On February 26th, 1963, the remaining narrow framed UTLX cars were sold to the Floyd W. Reed Co. of La Jara, Colorado, for scrapping.