The New Holland 6640 tractor engine horsepower is 90.7 hp | 67.6 kW, PTO horsepower is 76 hp | 56.7 kW, and the drawbar horsepower is 67.18 hp | 50.1 kW.
Engine HP90.7 hp | 67.6 kW
PTO HP76 hp | 56.7 kW
Drawbar HP67.18 hp | 50.1 kW
PTO Transfer83.8%
Torque337 lb-ft | 457.0 Nm
Displacement304 ci | 5.0 L
New Holland 6640 Horsepower Specs
Engine gross horsepower
90.7 hp | 67.6 kW
Engine net horsepower
85 hp | 63.4 kW
PTO horsepower claimed
76 hp | 56.7 kW
PTO horsepower tested
77.13 hp | 57.5 kW
Drawbar horsepower tested
67.18 hp | 50.1 kW
New Holland 6640 Useful Horsepower Calculations
PTO-to-engine power transfer
83.8% of engine hp reaches the PTO
Drawbar-to-engine power transfer
74.1% of engine hp reaches the drawbar
Drawbar-to-PTO power ratio
88.4% drawbar hp vs PTO hp
Engine size per PTO horsepower
4 ci per PTO hp
PTO horsepower per liter
15.2 PTO hp per L
Engine size per engine horsepower
3.4 ci per engine hp
Engine horsepower per liter
18.1 engine hp per L
Torque per PTO horsepower
4.4 lb-ft per PTO hp
Rated speed per PTO horsepower
28.9 rpm per PTO hp
New Holland 6640 Engine Specs
Displacement
304 ci | 5.0 L
Bore and stroke
4.40×5.00 inches | 112 x 127 mm
Compression
17.5:1
Rated RPM
2200
Torque
337 lb-ft | 457.0 Nm
Torque RPM
1200
New Holland 6640 Fuel, Cooling, Starting & Service Specs
Starter volts
12
Battery volts
12
Firing order
1-3-4-2
Idle RPM
725-2375
Intake valve clearance
0.016 inches (cold) | 0.406 mm
Exhaust valve clearance
0.019 inches (cold) | 0.483 mm
New Holland 6640 Horsepower Comparison Charts
Engine horsepower comparison
This model
90.7 hp
Average
80 hp
Low
45 hp
High
120 hp
PTO horsepower comparison
This model
76 hp
Average
65 hp
Low
35 hp
High
105 hp
Drawbar horsepower comparison
This model
67.2 hp
Average
55 hp
Low
30 hp
High
95 hp
Displacement comparison
This model
304 ci
Average
260 ci
Low
150 ci
High
380 ci
Torque comparison
This model
337 lb-ft
Average
240 lb-ft
Low
120 lb-ft
High
420 lb-ft
Rated RPM comparison
This model
2,200 rpm
Average
2,200 rpm
Low
1,800 rpm
High
2,700 rpm
Engine size per PTO HP
This model
4 ci/hp
Average
3.5 ci/hp
Low
2.2 ci/hp
High
5.8 ci/hp
Benchmarks use practical low, average and high ranges for the utility tractor category. Use the operator manual and actual engine/tractor configuration before sizing implements or judging working power.
New Holland 6640 Horsepower FAQ
How much horsepower does the New Holland 6640 have?
The listed engine output is 90.7 hp, above the 80 hp benchmark average. That is a higher-power result, so ballast, tire setup and implement width matter if you want to use the full 90.7 hp.
How much PTO horsepower does the New Holland 6640 have?
The listed PTO output is 76 hp, above the 65 hp benchmark average. That is the number to use for mowers, balers, augers, pumps and other PTO tools that need up to about 76 hp.
How much drawbar horsepower does the New Holland 6640 have?
The listed drawbar output is 67.2 hp, above the 55 hp benchmark average. That makes the 67.2 hp drawbar number more useful than engine hp for tillage and heavy pulling.
How much engine power reaches the PTO on the New Holland 6640?
The PTO-to-engine transfer works out to 83.8%, from 90.7 engine hp to 76 PTO hp. That is a normal usable range for judging PTO implement fit.
How efficient is the New Holland 6640 for pulling work?
The drawbar-to-engine transfer is about 74.1%, from 90.7 engine hp to 67.2 drawbar hp. That gives a more grounded pulling estimate than engine horsepower alone.
Is the New Holland 6640 better judged by PTO hp or drawbar hp?
The drawbar output is about 88.4% of PTO output, comparing 67.2 drawbar hp with 76 PTO hp. That helps separate pulling ability from PTO implement ability.
How big is the New Holland 6640 engine?
The engine displacement is 304 ci, above the 260 ci benchmark average. Bigger displacement can help low-rpm pull and load-holding feel.
Is the New Holland 6640 engine stressed for its PTO horsepower?
The engine has about 4 cubic inches per PTO hp, using 304 ci and 76 PTO hp. That points to a larger-displacement, lower-stress style setup.
How much PTO horsepower per liter does the New Holland 6640 make?
The output density is about 15.2 PTO hp per liter, using 76 PTO hp and 5 L of displacement. Higher hp/L means more output squeezed from each liter; lower hp/L usually means a more relaxed engine tune.
Official information note
Horsepower and engine specs can vary by year, market, engine option, fuel system, test standard and tractor configuration. Check the operator manual, spec plate, parts book and official newholland.com website before buying parts, sizing implements or making repair decisions.
