Rio Grande class K-37

  (Redirected from D&RGW K-37)

The Denver and Rio Grande Western K-37 is a class of 2-8-2 "Mikado" type narrow-gauge steam locomotives built for the Denver and Rio Grande Western Railroad. They were originally built by Baldwin as part of an order for thirty standard gauge 2-8-0 "Consolidation" type locomotives, class 190, in 1902. They were renumbered into class C-41 (meaning 41,000 lbs of tractive effort) during the railroad's reorganization in 1924 and were converted to 3 ft (914 mm) gauge in 1928-30 at the railroad's Burnham Shops in Denver, Colorado with many new parts including new frames and smaller drivers. They then became class K-37.

Denver & Rio Grande Western K-37
D&RGW SL 491 2008.jpg
D&RGW K-37 No. 491 on static display at the Colorado Railroad Museum
Type and origin
Dimensions are as rebuilt unless noted
Power typeSteam
BuilderBaldwin Locomotive Works
Build date1902
RebuilderD&RGW Burnham Shops
Rebuild date1928–1930
Number rebuilt10
 • WhyteOriginal: 2-8-0
Rebuilt: 2-8-2
 • UIC1′D1′ h2
GaugeOriginal: 4 ft 8+12 in (1,435 mm)
Rebuilt: 3 ft (914 mm)
Leading dia.Original: unknown
Rebuilt: 28 in (711 mm)
Driver dia.Original: 55 in (1,397 mm)
Rebuilt: 44 in (1,118 mm)
Trailing dia.Original: none
Rebuilt: 28 in (711 mm)
Wheelbase29 ft (8.8 m)
Length41.1 ft (12.5 m)
Width10.4 ft (3.2 m)
HeightEngine: 13.3 ft (4.1 m)
Tender: 13.5 ft (4.1 m)
Loco weight183,920 pounds (83,420 kg)
Fuel typeCoal (No. 493 converted to oil)
Boiler pressure200 psi (1.38 MPa)
Cylinder size20 in × 24 in (508 mm × 610 mm)
Valve gearWalschaerts
Loco brakeAir
Train brakesAir
Performance figures
Tractive effort37,100 lbf (165 kN)
OperatorsDenver & Rio Grande Western (D&RGW)
Durango & Silverton (D&SNG)
Cumbres & Toltec Scenic (C&TS)
Colorado Railroad Museum (C.R.R.M.)
ClassD&RG: 190
D&RGW: C-41
after rebuild: K-37
LocaleColorado and New Mexico
Retired1955 (No. 496), 1962–1968
PreservedEight (Nos. 491, 492, 493, 494, 495, 497, 498 and 499) preserved, two (Nos. 490 and 496) scrapped
RestoredNo. 491; August 2014
No. 493; January 24, 2020
No. 497; 1984
DispositionNos. 491 and 493 operational, No. 497 awaiting overhaul, Nos. 492 and 498 in storage, Nos. 494, 495 and 499 on display


The locomotives are of outside-frame design, with the driving wheels placed between the two chassis frames which support the boiler, but with the cylinders, driving rods, counterweights and valve gear on the outside. This general arrangement is shared with the earlier K-27, K-28 and K-36 Mikado type engines.


The locos worked out of Salida, Colorado to Gunnison, Colorado and up the Crested Butte Branch as well as the Monarch Branch. The locos also worked out of Alamosa, Colorado to Antonito over Cumbres Pass to Chama and on to Durango and the Farmington branch. Like the K-36s the locos were not permitted West of Gunnison or on the Silverton branch. However, the Silverton branch has since been upgraded to handle K-36s and K-37s. Three of the K-37s, Nos. 491, 493 and 499, were equipped with steam heat and signal lines so they could haul passenger trains like the San Juan Express and Shavano.

Of the eight preserved K-37s, locomotive #497 has operated on both the Durango and Silverton Narrow Gauge Railroad (D&SNG) in Durango, Colorado from 1984 to 1991 and on the Cumbres and Toltec Scenic Railroad (C&TSRR) in Chama, New Mexico from 1992 to 2002. In late 2002, #497 was taken out of service, and as of 2021, it currently sits inside the Chama roundhouse awaiting a future overhaul. In August 2014, locomotive #491 was restored to operating condition at the Colorado Railroad Museum (C.R.R.M.) and operated for the first time in public on Saturday, September 13, 2014 at the annual Thomas the Tank Engine event. A ticketed "roll out" was hosted on August 29, 2014. On May 4, 2016, the D&SNG, in cooperation with the Colorado Railroad Museum, transported locomotive #493 to Durango after resting in Silverton for almost 20 years with the plan of having the C.R.R.M. transport it to Golden, Colorado and have it restored as well. However, after plans with the C.R.R.M. fell through, the D&SNG decided to undertake the restoration of #493 themselves. In the restoration process of #493 however, the locomotive was converted to oil-firing, making it the first former D&RGW 2-8-2 to burn oil instead of coal, the next one being K-28 class #473.[3] On January 24, 2020, #493 moved under its own power for the first time in over 50 years, making it the first D&RGW K-37 class since #497 to run on the D&SNG. #493 then ran its first revenue run on the D&SNG on February 14, 2020.

K-37 Steam locomotive #493 in Silverton Yard.
K-37 #493 in Durango after being moved from Silverton.

Although the K-37s are actually about 2% lighter than the K-36s, they were erroneously thought to be much harder on track. The D&SNG originally owned four of the surviving K-37s, but they found that the #497 was too hard on their track and didn't handle the Animas Canyon section of the route as well as they would have hoped. Consequently, they traded #497 to the C&TSRR for K-36 #482 and #499 to Royal Gorge Park in Canon City for #486. However, the problems experienced by the D&SNG are now thought to have been isolated to locomotive #497's trailing truck and not universal to all K-37s.


The full roster of K-37 locos is:[4][5][6]

Class K-37
Class 190
Class C-41
490 1114 1014 20695 1928 n/a Retired in 1962.
Dismantled between 1963-64.
491 1126 1026 20829 1928 Colorado Railroad Museum, Golden, CO Retired in 1963.
It was acquired by History Colorado in 1970.
Then moved to the Colorado Railroad Museum in 1985; ownership of the engine was transferred to the museum in 2013.
Restored to operating condition and debuted on August 30, 2014.
492 1121 1021 20749 1928 C&TS To C&TS in 1970.
Stored in Chama, NM.
493 1105 1005 20550 1928 D&SNG Retired in 1968.
Moved to D&SNG in March 1981.
Restored to operating condition on January 24, 2020 as an oil-burning engine.
494 1120 1020 20748 1928 C&TS Retired in 1962.
To C&TS in 1970.
Currently on display in Antonito, CO.[7]
495 1104 1004 20522 1928 C&TS Retired in 1962.
To C&TS in 1970.
Currently on display in Antonito, CO.[8]
496 1123 1023 20751 1930 n/a Dismantled in 1955.
Subject of an April Fools' Day hoax in stating that it had been discovered intact in a barn near Salida, CO in 2011.[9]
497 1103 1003 20521 1930 C&TS To D&SNG in March 1981.
Restored to operating condition in 1984.
Traded to C&TS for K-36 No. 482 in October 1991.
Taken out of service in late 2002.
Currently stored in Chama, NM inside the roundhouse.
Awaiting a future overhaul.[10]
498 1109 1009 20640 1930 D&SNG To D&SNG in March 1981.
Stored in Durango, CO.
499 1125 1025 20753 1930 Royal Gorge Park
Canon City
Retired in 1970.
To D&SNG in March 1981.
Traded to Royal Gorge Park for K-36 No. 486 in May 1999 for display.


  1. ^ Armitage, Alan B. (October 1979). "Denver & Rio Grande Western's K-37 MIkados". Model Railroader. Milwaukee: Kalmbach: 70–73.
  2. ^ Official Roster No. 11 of the Denver and Rio Grande Western Railroad System. Denver: The Denver and Rio Grande Western Railroad System. April 1, 1923. p. 94.
  3. ^
  4. ^ "Denver & Rio Grande Western Mikados". Steam Locomotive dot com. Archived from the original on 21 September 2010. Retrieved 12 February 2010.
  5. ^ "Denver & Rio Grande Western Roster". Rio Grande Modeling & Historical Society. Archived from the original on 22 November 2008. Retrieved 12 February 2010.
  6. ^ "Durango & Silverton Steam". Retrieved 12 February 2010.
  7. ^ "2014 Trip - Alamossa & South Along U.S. 285 - Franks-Focus". Retrieved 2018-05-04.
  8. ^ "K-37 #495". Retrieved 2018-05-04.
  9. ^ "Historic Steam Engine discovered in Barn". March 29, 2011. Retrieved December 20, 2011.
  10. ^ "Chama and Durango". Retrieved 2018-05-04.