UP #3985 Challenger Departing Kansas City

UP#3985 4-6-6-4 Challenger back in the day.

Built specifically to take on long grades like her cousins the “Big Boys” 4-8-8-4’s, the #3985 Challenger was designed to pull freight fast up long grades without helper engines.

Currently, UP’s #3985 Challenger 4-6-6-4 is undergoing renovation as Union Pacific’s steam shop in Cheyenne, Wyoming.

Since the #3985 was so long, she was built as an articulated locomotive that allows the 4 wheel front truck to go with the bend in tracks which would have otherwise be troublesome to such a long boiler. Hence, she can articulate herself around the curves because the front of the boiler sits on top of this truck much the same way a big rig diesel truck hooks up to its’ trailer.

Some quick facts about the UP #3985 Challenger

• Builder – American Locomotive Works – 1943
• Wheel configuration – 4-6-6-4
• Locomotive and tender weight – 1,073,900 lbs
• Tractive effort – 97,350 lbf
• Nicknamed – Challenger

Let us know if you have ever had a chance to see UP #3985 in action! We would love to hear about your experience!