loco-info.com
The reference for locomotives and railcars
Navigation
Random
Search
Compare
Settings
Duluth, Missabe & Iron Range classes M-3 and M-4
United States | 1941 | 18 produced
M3 No. 221
M3 No. 221
Missabe Railroad Historical Society

For heavy ore trains with up to 115 cars, the Duluth, Missabe & Iron Range needed more powerful locomotives, where the most difficult task was to pull the empty trains up the 2.2 percent steep ramp from the port in Duluth to the marshalling yard in Proctor. The Western Pacific class M-137 was taken as the basis. With a two-axle trailing bogie, the wheel arrangement was 2-8-8-4 "Yellowstone", which allowed for a larger firebox and a larger all-weather cab for the cold Minnesota winters.

In 1941 eight members of the M-3 class were built and in 1943 ten more M-4s. Since the DM&IR had less traffic volume in winter, some of the locomotives were leased out. They were particularly valued by the D&RGW, where they had to pull heavy freight trains over a 10,239 foot high pass over the Continental Divide. With the exception of one locomotive that had an accident, all remained in use until they were replaced by diesel locomotives between 1958 and 1963. Today three remain, all of which are no longer operational.

General
Built1941, 1943
ManufacturerBaldwin
Axle config2-8-8-4 (Yellowstone (Mallet)) 
Gauge4 ft 8 1/2 (Standard gauge)
Dimensions and Weights
Wheelbase67 ft 2 in
Fixed wheelbase17 ft 3 in
Total wheelbase113 ft 6 in
Service weight695,040 lbs
Adhesive weight560,257 lbs
Total weight1,133,040 lbs
Axle load70,033 lbs
Water capacity25,000 us gal
Fuel capacity54,000 lbs (coal)
Power
Power sourcesteam
Estimated power6,000 hp (4,474 kW)
Optimal speed27 mph
Starting effort140,093 lbf
Power Plant
Driver diameter63 in
Boiler pressure240 psi
Expansion typesimple
Cylindersfour, 26 x 32 in
Boiler
Grate area125 sq ft
Firebox area750 sq ft
Tube heating area6,032 sq ft
Evaporative heating area6,782 sq ft
Superheater area2,770 sq ft
Total heating area9,552 sq ft
Calculated Values
steam locomotive
freight
Articulated
last changed: 02/2024
loading...

We use cookies to save the following settings:

  • selected navigation structure
  • selected language
  • preferred units
  • spelling of railway company names

If you refuse the use of cookies, the settings will only be retained for the current session and will be reset to the default values the next time you visit the site.

Display of units

Here you can set the desired unit system for the technical data.

  • Metric: Lengths in meters, weights in tonnes, and volumes in cubic meters
  • Imperial (UK): Lengths in feet/inches, weights in long tons and volumes in imperial gallons
  • Imperial (US): Lengths in feet/inches, weights in pounds, and volumes in US gallons
  • Individual: Depends on the country of origin of each locomotive
Operator names

Here you can set the display of railway company names.

  • Short: Abbreviation or short form of the name
  • Standard: commonly used name, partially translated to English
  • Complete: full name in local language