From inside (document excerpt):
Groundsmaster 5900/5910 Specifications* ® GROUNDSMASTER 5900, MODEL 31598, GROUNDSMASTER 5910 MODEL 31599 ENGINE COOLING SYSTEM FUEL SYSTEM CAPACITIES TIRES/WHEELS INSTRUMENTATION POWERTRAIN PRODUCTIVITY CONTROLS Cummins® QSB3.3, 4 cylinder, turbocharged, intercooled. HP: 99* @ 2630 (73.8 kW), Torque @ rpm (lb.-ft.) 306 @ 1600 (415 N·m) Displacement 199 cu in (3 3 L), Fuel Injection; electronic high-pressure common rail SmartCoolTM System – Variable speed, temperature actuated reversing fan; Top and rear intake; Oil cooler tilts out for service access; Radiator cross flow, 4 row Intercooler cools air from turbo for improved power, fuel economy and emmissions control Diesel Biodiesel compatible up to B20 Fuel: 35 gal Hydraulic: 19 gal (72 L) Engine Oil: 8 5 qt (8 L) w/filter Coolant: 5900 13 5 qt (12 8 L) 5910 18 0 qt (17 0 L) Front: 29 x 1 2 50-15, 10 ply Rear: 23 x 10 50-12, 6-ply InfoCenterTM : Onboard LCD display shows gauges, alerts/faults, service reminders, electrical system diagnostics Indicates fuel level, coolant temp , low oil pressure, alternator, engine hours, engine rpm, hydraulic oil temp, voltage 4 wheel drive; parallel hydrostatic, closed loop; traction drive pump; variable displacement piston, servo control Front drive: planetary gear type, double reduction Rear drive: high torque, low speed hydraulic motors Traction assist: front and rear hydraulic flow divider, steering brakes Infinitely variable speed Forward speeds: mow: 0-10 8 mph (17 4 km/h) transport: 0-20 mph (0-32 2 km/h) Reverse speeds: mow 0-5 7 mph (0-9 2 km/h), transport: 0-10 5 mph (0-16 9 km/h) transport Speed control: Electronic, limits max speed Maximum mow rate: 20 77 acres/hr (8 4 ha)* Typical mow rate: 9 6 acres/hr (3 9 ha)