Southern Pacific Railroad diesel locomotive number 6583 at Seattle, Washington on April 09, 1972. SP 6583 and another unit at Balmer yard in the Interbay district of Seattle in 1972. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, freight yard.

Southern Pacific Railroad diesel locomotive number 6387 at Tacoma, Washington on October 22, 1967. SP 6387 passes UP Junction with a northbound freight train in Tacoma in 1967. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, freight train.

Southern Pacific Railroad diesel locomotive number 6387 at Tacoma, Washington on October 22, 1967. SP 6387 passes Reservation with a northbound freight train in Tacoma in 1967. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, freight train.

Southern Pacific Railroad diesel locomotive number 4420 at Hillsboro, Oregon in 1987. SP 4420, an SD9 in the Kodachrome paint colors, parked in Hillsboro in 1987. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive.

Southern Pacific Railroad diesel locomotive number 4420 at Hillsboro, Oregon in 1987. SP 4420, an SD9 in the Kodachrome paint colors, with a cut of cars at Hillsboro in 1987. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, center-beam flat car.

Southern Pacific Railroad diesel locomotive number 4414, circa 1987. SP 4414 parked in a community. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive.

Southern Pacific Railroad diesel locomotive number 4388 at Mt. Shasta, California in August 1977. SP 4388, 9054 and a third unit lead an extra freight train north of Mt. Shasta in 1977. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, freight train.

Southern Pacific Railroad diesel locomotive number 4370 at Eugene, Oregon on May 30, 1974. SP 4370 and caboose 1214 make a hoop at Eugene in 1974. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, steel caboose.

Southern Pacific Railroad diesel locomotive number 4368 in 1987. SP 4368, an SD9, parked on an industrial siding. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive.

Southern Pacific Railroad diesel locomotive number 4000 at Redwood City, California on August 10, 1973. SP 4000 with caboose 1440 at Redwood City in 1973. Photo by J.M. Fredrickson. Other Subject Classes: diesel locomotive, steel caboose.