A westbound Union Pacific “van” train, led by EMD DDA40X “Centennial” No. 6917, approaches Dale Junction on a desolate spring day on Wyoming’s Sherman Hill in April 1984.

Way back when, if the Union Pacific was power short, even the #6936 was available for freight service. Here is proof as the big DDA40X gets the NPLAV-15 underway westbound at Green River, WY. Scan... (more)

UP 3692 leads 3 Centennials around the curve at Summit. Prior to this shot this train had coupled onto the rear of another train and shoved it to the summit as well.

Westbound Union Pacific DDA40X 6929 leaving Cheyenne, Wyoming. A Mike Bledsoe Photo.

UP Centennial 6936.

Union Pacific 6900 Series Centennials DDA40X 6600hp. (6900-6946) built between 4/69 - 9/71. Equipped with two 16-645E3A Diesel Engines, Fuel tank 8200 Gals, (2) 4-axle "D" truck assembly. Length... (more)

An eastbound Union Pacific engineering special approaches Tunnel 1 at Plainview, Colorado, on the afternoon of August 13, 2003. The 11-car passenger train is powered by impressive EMD DDA40X “Ce... (more)

Four Union Pacific DDA40X Centennials stored with GP30B's/SD24A's and B's at UP's Yermo Yard, near Barstow, California.

UP 6938 was retired on May 25, 1985 and was cosmetically restored to be put on display in front of the Jenks Shops where it still sits today.

The Centennials were the largest diesel electric locomotives ever built comprising of two engines on one frame they delivered 6,600 horsepower and were only designed and built for the Union Pacifi... (more)

”Someday, This Will Be Mine!”

An aspiring young engineer holds onto the handrail of one of the world’s largest diesel locomotives as he poses for a portrait. In a few short h... (more)

Union Pacific EMD DDA40X No. 6938 sits on display in front of the railroad’s Downing B. Jenks Shop at North Little Rock, Arkansas, on May 8, 2014.

Two UP DDA40X "Centennials" 6922 and 6929 at Council, Bluffs, Iowa in August 1980. No photographer listed on slide.

Union Pacific EMD DDA40X “Centennial” No. 6936 powers a westbound engineering passenger special curving through Pinecliffe, Colorado, on October 4, 2001.

A Union Pacific officer special rolls along the Sacramento River on a summer afternoon. In 1997, the railroad was washed away here by floodwaters.