Double Wheel Slip On Big Boy And UP 844!

Continuing their journey out of Harriman, Wyoming, these two locos encounter the same tractive difficulty.

Note the diameter of the driving wheels on Big Boy compared to UP 844

The smaller 68 inch diameter Big Boy drivers were meant for more power compared to the 80 inch drivers on UP 844 which were meant for speed.

Of the 25 Big Boys that were built, all but 8 were scrapped, unfortunately.

h3>Some Quick Facts about UP #844

• Rail Line: Union Pacific
• Power type: 4-8-4 Steam Locomotive FEF-3 class Northern
• Builder: American Locomotive Company
• Locomotive and tender weight: 907,890 lbs
• Driver diameters – 80 inches!
• Tractive effort: 63,750 lbf
• MAX SPEED – 120 MPH !

Quick Facts about UP Big Boy 4014

• Rail Line: Union Pacific
• Driver diameters:-68 inches
• Power type: 4-8-8-4 Steam Locomotive Class 4000
• Builder: American Locomotive Company 1941
• Coal Consumption: 22,000 lbs per hour (converted to oil)
• Locomotive and tender weight: 1,250,000 lbs
• Max Speed: 80 MPH !

Let us know if you have seen these two locomotives in person. We would love to hear about your experience!