The Case IH D40 tractor engine horsepower is 40 hp | 29.8 kW, and PTO horsepower is 35 hp | 26.1 kW.
Case IH D40 Horsepower Specs
| Engine gross horsepower | 40 hp | 29.8 kW |
|---|---|
| PTO horsepower claimed | 35 hp | 26.1 kW |
Case IH D40 Useful Horsepower Calculations
| PTO-to-engine power transfer | 87.5% of engine hp reaches the PTO |
|---|---|
| Engine size per PTO horsepower | 3.5 ci per PTO hp |
| PTO horsepower per liter | 17.5 PTO hp per L |
| Engine size per engine horsepower | 3 ci per engine hp |
| Engine horsepower per liter | 20 engine hp per L |
| Rated speed per PTO horsepower | 74.3 rpm per PTO hp |
Case IH D40 Engine Specs
| Displacement | 121.7 ci | 2.0 L |
|---|---|
| Bore and stroke | 3.31×3.54 inches | 84 x 90 mm |
| Rated RPM | 2600 |
Case IH D40 Fuel, Cooling, Starting & Service Specs
| Starter volts | 12 |
|---|---|
| Battery volts | 12 |
Case IH D40 Horsepower Comparison Charts
Engine horsepower comparison
PTO horsepower comparison
Displacement comparison
Rated RPM comparison
Engine size per PTO HP
Benchmarks use practical low, average and high ranges for the compact and small utility tractor category. Use the operator manual and actual engine/tractor configuration before sizing implements or judging working power.
Case IH D40 Horsepower FAQ
How much horsepower does the Case IH D40 have?
The listed engine output is 40 hp, above the 35 hp benchmark average. That is a higher-power result, so ballast, tire setup and implement width matter if you want to use the full 40 hp.
How much PTO horsepower does the Case IH D40 have?
The listed PTO output is 35 hp, above the 28 hp benchmark average. That is the number to use for mowers, balers, augers, pumps and other PTO tools that need up to about 35 hp.
How much engine power reaches the PTO on the Case IH D40?
The PTO-to-engine transfer works out to 87.5%, from 40 engine hp to 35 PTO hp. That is a normal usable range for judging PTO implement fit.
How big is the Case IH D40 engine?
The engine displacement is 121.7 ci, close to the 110 ci benchmark average. It is close to the normal engine-size range for this horsepower class.
Is the Case IH D40 engine stressed for its PTO horsepower?
The engine has about 3.5 cubic inches per PTO hp, using 121.7 ci and 35 PTO hp. That points to a larger-displacement, lower-stress style setup.
How much PTO horsepower per liter does the Case IH D40 make?
The output density is about 17.5 PTO hp per liter, using 35 PTO hp and 2 L of displacement. Higher hp/L means more output squeezed from each liter; lower hp/L usually means a more relaxed engine tune.
What rpm is the Case IH D40 rated at?
The rated speed is 2,600 rpm, close to the 2,400 rpm benchmark average. The 2,600 rpm figure is around normal for this class.
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 caseih.com website before buying parts, sizing implements or making repair decisions.
