Locomotive Phases - EMD GP59, GP60

The GP60 was introduced in 1985 (near the end of GP40-2 and GP50 production) and featured EMD's new 710 series engine. As a result of the increasing preference for six-axle locomotives that began in the 1970s, the GP60 was EMD's last high-horsepower four-axle unit in a series of visually similar models that started with the GP40 in 1965. The raised, boxy dynamic brake housing of the GP60 is the most obvious visual distinction from earlier models. The GP59 used an engine with 12 cylinders (rather than 16 in the GP60) but was otherwise much the same.

Transition: From GP50 to GP60

The GP59/GP60 retained many of the dimensions and details of the late GP50. However, the overall length was increased by 7" from 59' 2" to 59' 9", with the added length visible in the exhaust stack housing and first two hood doors. The rear truck was also moved rearward by 6" relative to the rear pilot face, which (when combined with the frame length) increased the truck centers from 34' to 35' 1". The added length allowed for a larger fuel tank, although the larger tank was not used on all GP60 production.

On the hood of the GP59/GP60, the area housing the inertial air intake and blower duct was slightly enlarged, creating a raised jog in the roofline about 1.25" high. Accordingly, the inertial air intakes were moved up and the blower duct height was increased. The central hood doors were made taller, and the dynamic brake hatch was modified into a taller, boxier design. At the rear of the hood, the radiator intakes and fans remained largely the same, but the hood doors were changed from a grouping of 2-2-2-1 to a grouping of 1-4-2 (except for early GP59 units, which had a 1-4-3 grouping).

Phases

These phases are based on the GP59, GP60, GP60B and GP60M rosters compiled by Robert Sarberenyi. While I've tried to be consistent with those phases, I've elected to remove Sarberenyi's Phase 2c2 and Phase 2e descriptions because the build dates placed them out-of-order with respect to other phases, and both phases were unique to a single railroad order.

Phase 1: 1985.06 - 1985.10

• Cab/short hood: non-standard, rounded corners, pointed windshield
• Dynamic brake housing: rounded top edge, angled intake
• Center hood doors: 7 latched
• Rear hood doors: 5 latched
• Dynamic brake access panel: latched
• Handbrake housing: Flush

Phase 2a: 1988.02 - 1988.10

• Cab/short hood: standard (as on late GP50)

Phase 2b: 1989.07 - 1989.12

• Dynamic brake housing: angular edges, vertical intake
• Lift ring ahead of radiators moved from roof to hood side

Phase 2c: 1990.03 - 1990.09

• Center hood doors: 5 latched
• Rear hood doors: 4 latched
• Dynamic brake access panel: bolted

Phase 2d: 1991.01 - 1994.01

• Handbrake housing: recessed

Roster

This roster is based on my own observations in conjunction with the GP59, GP60, GP60B and GP60M rosters compiled by Robert Sarberenyi and production information from the Unofficial EMD Homepage.