SP SD38-2 2975 is one of six units built (in April 1973) for use on then-new West Colton Yard's hump. It is seen here, teamed with slug 100 and SD38-2 2971, on July 16, 1973, shortly before the official opening of the yard. Note the lack of typical SP warning lights. Following the merger with Union Pacific, this engine became UP 834.