Harvest Horsepower
Know Your Power— Engine vs. PTO
Horsepower ratings can look straightforward on a spec sheet, but tractors speak two different power languages and understanding both will save you money and frustration.
• Engine Horsepower: is the headline number, the total muscle the engine produces. It tells you how much raw power the tractor can generate before anything is transferred to the drivetrain.
• Power Take-Off Horsepower: Power take-off( PTO) is the usable power that actually reaches your implements through the PTO shaft. Because energy is lost to the transmission and hydraulics, PTO horsepower is always lower— typically by 10 % to 20 %.
Why it matters: Every implement you buy— from a rotary cutter to a baler— will list a minimum PTO requirement, not engine horsepower. A round baler rated for 55 PTO hp usually demands an engine closer to 65 hp to 70 hp to maintain that output once power losses are factored in. Undershoot that number and you risk stalling in heavy windrows, overloading the engine or prematurely wearing clutches and belts.
A quick rule of thumb: Match the implement’ s PTO spec and add a 10 % to 15 % buffer when choosing engine horsepower. That margin keeps you from running the tractor at full throttle all day, improves fuel efficiency and gives you a cushion for future attachments that might draw a little more power than today’ s lineup.
What Each Class Really Delivers
Tractor class affects more than raw power— it shapes your implement options, storage needs and operating costs.
• Compact Utility( 20 hp to 50 hp) costs from $ 18,000 to $ 35,000 new. These burn 1 to 2 gallons of diesel per hour and fit in a standard barn bay. They are ideal for small-acre vegetable or livestock farms where versatility and maneuverability trump brute strength.
October 2025 | www. FarmersHotLine. com | 11