Looking more like a model locomotive, the last operating Union Pacific Centennial DD40X, UP 6936 East, is seen in a pan shot from an ice covered farm road just east of Round Grove, Illinois on Feb... (more)

UP Engineering Special SYCPB-16 arrives in Villa Grove, IL only minutes off its scheduled time.

The one and only operatable DDA-40X, UP 6936, heads south through St. Anne.

Dropping into the high desert, the Wimmer Engineering special passes under the SP signal bridge at milepost 377 on the UP's Mojave Sub.

UP DDA40X CENTENNIAL 6936 in Freight Service - 1976. UP DDA40X 6936, UP SD40-2H "Fast Forty" 8012 and UP DDA40X 6923 westbound on priority TOFC. During the mid to late 1970s, two Centennial... (more)

Following a passenger stop in downtown Tehachapi, the Wimmer special has returned to high speed running as the train approaches SR 58 at Sand Canyon.

Nearing the top of the grade, the Wimmer special approaches Highway 202 and downtown Tehachapi where a brief station stop will be made to disembark several passengers.

The Wimmer special continues the uphill climb at the Tehachapi Loop with ex-SP office car Sunset coupled behind the UP 6936.

Sun tries to break through the cloud cover at Woodford as the Wimmer special works its way south on the UP's Mojave Sub.

Climbing higher into the Tehachapi mountains, UP 6936 heads into Tunnel 3 just around the bend from the south switch at Bealville.

Despite its long wheelbase, the big Centennial takes the sharp curve into Tunnel 2 with ease as it powers the Wimmer Engineering special across the Tehachapi mountains.

Under gloomy skies in the Tehachapi mountains, the Wimmer special approaches a work site at Ilmon on the UP's Mojave Sub.

Passing Slater on the UP's Fresno Sub, the Wimmer Engineering special nears Bakersfield where the train will change crews before heading into the Tehachapi mountains.

Handling a Bill Wimmer Engineering special, UP 6936 has the inspection train moving along at track speed as it passes the south switch Delfar on the UP's Fresno Sub.

UP 6936 leads a westbound business train out of rock tunnel 25 at Rich Bar, deep in the heart of the Feather River Canyon.