While later models would improve on the 4-8-4's limitation

Flywheel equipped motor

Model Number: 60605

Model Number: 71154

The locomotive is modeled to show streamlined sheathing of the smoke box

MTH 20-21264-1 Union Pacific SD70ACe Diesel Engine w/P-S 3 #1111 (Hi-Rail) VariantsUnitPrice_number_118.49 While later models would improveThis is an MTH 20 21264 1 O Union Pacific SD70ACe Hi Rail Wheels Diesel Locomotive with Proto Sound 3. 0 #1111. Features: Intricately Detailed, Durable ABS Body, Diecast Truck Sides, Pilots and Fuel Tank, Metal Chassis, Metal Handrails and Horn, Moveable Roof Fans, Metal Body Side Grilles, Detachable Snow Plow, (2) Handpainted Engineer Cab Figures, Authentic Paint Scheme, Metal Wheels, Axles and Gears, (2) Remote Controlled Proto Couplers, O Scale