UP 1826 (SD40N) moves with two other light power units through the North Yard in Denver, Colorado.

A variety of Union Pacific motors spotted in the North Yard in Denver, Colorado.

UP 1826 (SD40N) gets ready to pull a cut of cars out of the Union Pacific's North Yard for sorting.

UP 1826 (SD40N) works shuffling cars in the North Yard in Denver, Colorado.

UP 1826 (SD40N) has yard sorting duty as it heads into the North Yard for another cut of cars.

UP 1826 (SD40N) works the Union Pacific's North Yard in Denver, Colorado.

UP 1826 (SD40N) works the North Yard in Denver, Colorado as other engines are getting service.

UP 1826 (SD40N) shoves a cut of cars back into the North Yard in Denver, Colorado.

UP 1826 (SD40N) works a cut of cars in the North Yard in Denver, Colorado.

UP 1826 (SD40N) works the North Yard in Denver, Colorado. SD40N's seem to be the preferred motor for shuffling the cars.

UP 1826 (SD40N) shuffles a cut of oil cans in the Union Pacific's North Yard in Denver, Colorado.

UP 1826 (SD40N) moves a cut of cars in the North Yard in Denver, Colorado.

Union Pacific EMD SD40N (rebuilt SD40-2) No. 1826 has some work done in the Diesel House at the railroad’s former Rio Grande Burnham Shops on December 17, 2015.

UP 1826 (SD40N) works the North Yard in Denver, Colorado.

UP 1826 (SD40N) muscles a cut of cars back into the North Yard in Denver, Colorado.