Introduction
Nuffield PM-4 Utility Tractor
The Nuffield PM-4 is a two-wheel drive utility tractor manufactured in Birmingham, England, between 1950 and 1957. Designed for general agricultural tasks, this model represents the post-war era of British tractor engineering.
Engine and Performance
The tractor is powered by a Morris Motors 4-cylinder gasoline engine with a 3.8-liter (230 ci) displacement. It utilizes a liquid-cooled vertical L-head configuration and an oil bath air cleaner. The engine delivers 40.8 hp (30.4 kW) at a rated speed of 2000 RPM, producing 226 lb-ft (306.5 Nm) of torque at 950 RPM. A compression ratio of 6:1 is maintained, and the cooling system has a capacity of 18 quarts (17.0 L).
Transmission and Drivetrain
The drivetrain features a manual gear transmission providing 5 forward speeds and 1 reverse speed. Power is transmitted through a 280mm dry disc clutch. Steering is manual, and the tractor is equipped with independent mechanical expanding band brakes to ensure control during operation.
Hydraulics and PTO
The hydraulic system is of the open-center type, operating at a pressure of 1200 psi (82.7 bar). From 1955 onwards, the system pressure was increased to 2000 psi (137.9 bar). The rear PTO operates at a standard 540 RPM at an engine speed of 528 RPM.
Dimensions and Chassis
The PM-4 has a wheelbase of 78 inches (198 cm) and an overall length of 121.7 inches (309 cm). The operating weight is 5,307 lbs (2407 kg), which can be increased to 7,765 lbs (3522 kg) with ballast. The tractor features adjustable tread widths, with the rear tread ranging from 53.2 to 88.2 inches (135 to 224 cm) and the front tread from 52.8 to 70.9 inches (134 to 180 cm). Ground clearance is 21 inches (53 cm) at the frame.
Conclusion
With its 40 hp gasoline engine and adjustable tread widths, the Nuffield PM-4 is a versatile utility tractor suited for varied field operations and general farm maintenance tasks typical of the 1950s.
Production Information of Nuffield, PM-4
- Utility tractor
- Built in Birmingham, England
| Manufacturer | Nuffield |
|---|
Dimension and Tires Information of Nuffield, PM-4
| Rear tread | 53.2 to 88.2 inches [135 to 224 cm] |
|---|---|
| Wheelbase | 78 inches [198 cm] |
| Operating weight | 5,307 lbs [2407 kg] |
| Height (exhaust) | 80.7 inches [204 cm] |
| Length | 121.7 inches [309 cm] |
| Clearance (front axle) | 17 inches [43 cm] |
| Ballasted weight | 7,765 lbs [3522 kg] |
| Height (hood) | 59.5 inches [151 cm] |
| Front tread | 52.8 to 70.9 inches [134 to 180 cm] |
| Clearance (drawbar) | 21.4 inches [54 cm] |
| Ground clearance | 21 inches (at frame) [53 cm] |
| Ag front | 6.00-16 |
|---|---|
| Ag front(optional) | 14.00-30 |
| Ag rear | 13.00-30 |
| Ag rear | 11.00-36 |
| Ag rear(optional) | 9.00-36 |
| Ag front | 7.50-18 |
Engine Specifications of Nuffield, PM-4
- Morris Motors
- Liquid-cooled vertical L-head
- 4-cylinder
- Gasoline
| Air cleaner | Oil bath |
|---|---|
| Torque | 226 lb-ft [306.5 Nm] |
| Displacement | 230 ci [3.8 L] |
| Bore/Stroke | 3.937x4.724 inches [100 x 120 mm] |
| Power | 40.8 hp [30.4 kW] |
| Rated RPM | 2000 |
| Compression | 6:1 |
| Coolant capacity | 18 qts [17.0 L] |
| Starter volts | 12 |
| Torque RPM | 950 |
Transmission Information of Nuffield, PM-4
Transmission variants 1
| Type | Gear |
|---|---|
| Gears | 5 forward and 1 reverse |
| Clutch | 280mm dry disc |
Mechanical Specs of Nuffield, PM-4
- Two-wheel drive
- Open operator station.
- Manual steering
- Independent mechanical expanding band brakes
Power Information of Nuffield, PM-4
| Rear PTO Type | 540 (1.375) |
|---|---|
| Engine RPM | 528@1400 |
Hydraulics Specifications of Nuffield, PM-4
| Type | Open center |
|---|---|
| Pressure | 1200 psi [82.7 bar] |
| Pressure(optional) | 2000 psi (1955 onward) [137.9 bar] |
Where it sits
With 40 HP, the Nuffield PM-4 sits between M4 (38 HP) and 3/42 (42 HP) in Nuffield's range. Its power puts it in the 55th percentile of 1950s models in our database (592 machines).
Frequently asked questions
How much horsepower does the Nuffield PM-4 have?
The Nuffield PM-4 delivers 40 HP.
What years was the Nuffield PM-4 produced?
The Nuffield PM-4 was produced in 1950-1957.
What engine does the Nuffield PM-4 have?
The Nuffield PM-4 is powered by a Gasoline, 4-cylinder engine.
What transmission does the Nuffield PM-4 use?
The Nuffield PM-4 uses a Gear transmission.
How much does the Nuffield PM-4 weigh?
The Nuffield PM-4 weighs 5,307 lbs [2407 kg].
Is the Nuffield PM-4 4WD?
The Nuffield PM-4 is available in 2WD.