Agrimanual Workshop Centre

Repair, restoration, maintenance and technical information for agricultural and construction machinery.

Ford TW Series – TW-10, TW-15, TW-20, TW-25, TW-30 & TW-35

The Ford TW Series represents some of Ford’s best-known large tractors, combining six-cylinder diesel power with heavy transmissions, hydraulic PTO systems and serious field capability.

Machine of the Month

This guide covers the family in general. Engines, transmissions, hydraulics, PTO systems, axles, brakes, electrical equipment and production details can vary by model, market and serial range. Use the exact workshop manual for all pressure, torque, timing, clearance and adjustment data.

1. The Ford TW Range

The TW series represented Ford’s larger high-horsepower tractors. Well-known models include TW-10, TW-15, TW-20, TW-25, TW-30 and TW-35, with important differences between generations.

2. Identification and Generation Changes

Record model, serial number, engine number, transmission type, front axle and cab specification. Later Series II and related updates can differ significantly from earlier machines.

3. Six-Cylinder Diesel Engines

These tractors are known for large six-cylinder diesel engines. Check cold starting, oil pressure, blow-by, turbo condition, fuel system and coolant condition.

4. Turbocharger and Air System

Inspect air filter, compressor inlet, boost hoses, intercooler where fitted, exhaust manifold and turbo oil feed/drain. Black smoke under load can be caused by air restriction or boost leakage as well as fuel-system problems.

5. Fuel Injection

Mechanical injection systems depend on clean fuel, correct timing and sound injectors. Before condemning the pump, check supply pressure, filters, air leaks and injector condition.

6. Cooling System

Large tractors under heavy field load can expose marginal cooling systems quickly. Check radiator cleanliness, fan system, thermostat, water pump, hoses and coolant quality.

7. Transmission Options

TW tractors were produced with different transmission arrangements depending on model and year. Identify the exact gearbox before pressure testing or splitting the tractor.

8. Dual Power

Many Ford tractors of this era may be equipped with Dual Power, providing a hydraulically controlled ratio change. Faults can involve pressure, clutch packs, valves, seals and control linkage.

9. Dual Power Slips When Hot

Possible causes include internal leakage, worn clutch packs, low pressure, incorrect oil or pump/control-valve wear. Test pressure before dismantling.

10. Main Clutch and Drive

Check clutch slip, drag, release adjustment and driveline noises. On heavy tractors, worn splines and coupling components can also cause drive complaints.

11. PTO

Independent PTO systems may use hydraulic clutch packs and brakes. Check engagement pressure, control valve, brake operation and clutch-pack condition.

12. Closed-Centre / Load-Sensing Hydraulics Where Applicable

Hydraulic system design varies by model and generation. Confirm the exact pump and control arrangement before fitting auxiliary valves or changing relief settings.

13. Three-Point Linkage

Check position and draft control, lift capacity, response speed and holding ability. Weak lift hot can indicate pump wear or internal leakage.

14. Remote Valves

Check couplers, spool detents, flow control and internal leakage. Continuous pressure loss through a leaking remote can heat the hydraulic system.

15. 4WD Front Axle

Inspect front differential, hub reductions, prop shaft, 4WD clutch/control, steering joints and approved tyre matching.

16. Front Axle and Tyre Matching

Incorrect front-to-rear rolling circumference can create wind-up and accelerated axle wear. Use approved tyre combinations for the exact model.

17. Steering

Hydrostatic steering faults may involve priority valves, pump supply, steering unit, cylinders or front-axle wear.

18. Brakes

Check pedal balance, wet-disc condition where fitted, parking brake, transmission oil contamination and linkage/control condition.

19. Cab and Electrical Systems

Inspect charging system, cab earths, lighting, heater/blower, instrumentation and wiring around transmission and PTO controls.

20. Buying a Ford TW

  • Cold start and blow-by
  • Turbo and exhaust smoke
  • All transmission ratios and Dual Power
  • PTO under load
  • Hydraulics hot and cold
  • 4WD and axle leaks
  • Brake performance
  • Cab electrical condition

21. Restoration Priorities

  1. Identify exact generation.
  2. Service engine/cooling system.
  3. Test transmission and Dual Power pressures.
  4. Service hydraulics and PTO.
  5. Repair 4WD, steering and brakes.
  6. Tidy cab electrics.
  7. Finish cosmetics last.

Related Agrimanual Manuals

Machine of the Month conclusion

Ford TW tractors are still capable working machines, but their size makes guessing expensive. Pressure testing the transmission, PTO and hydraulic systems before dismantling can prevent major unnecessary repair costs.