ISO 4004:1983

Overview - ISO 4004:1983 (Agricultural tractors and machinery - Track widths)

ISO 4004:1983 specifies guideline track widths for agricultural tractors and self‑propelled machinery used in fields for row‑crops. Published as the first edition in 1983, it cancels and replaces ISO/TR 4004‑1975. The standard is intended as a manufacturer guideline for the principal driven axle(s) and does not apply to special‑type tractors, walking tractors, single‑axle motor‑driven machines, two‑wheeled propulsion units, or other agricultural machinery of special types.

Key topics and requirements

• Scope and applicability
  • Applies to principal driven axle(s) of wheeled tractors and to self‑propelled agricultural machinery used in row‑crop fields.
  • Excludes special types (walking tractors, single‑axle machines, two‑wheeled propulsion units, etc.).
• Preferred track widths
  • The standard lists preferred track widths with tolerances:
    • 1500 ± 25 mm
    • 1800 ± 25 mm
    • 2000 ± 25 mm
  • Note: ISO 4004 is a guideline; it is not expected that every machine be adjustable to all three widths.
• Definitions
  • Track (tread) of a wheeled tractor: distance at ground level between the median planes of the wheels on the same axle (for twin wheels, between the median planes of the pairs).
  • Track of track‑laying tractors: distance between the median planes of the tracks.
  • These definitions draw on ISO 789/1 terminology.
• Design implications
  • Track width dimensions and tolerances are intended to guide wheel/track positioning, axle design and crop‑row compatibility.

Applications - who uses ISO 4004 and why

• Tractor and agricultural machinery manufacturers - to design axles, wheel assemblies and adjustability options that match common row‑crop spacing and market expectations.
• Agricultural equipment designers and OEM engineers - to standardize product families and ensure compatibility with implements and crop rows.
• Procurement and fleet managers - to specify equipment that aligns with field cultivation patterns and inter‑operability across implements.
• Testing laboratories and certification bodies - for dimensional verification and conformity checks against internationally recognized track width guidelines.
• Agricultural consultants and engineers - to advise on machine selection and retrofit options for row‑crop systems.

Related standards

• ISO 789/1 - Definitions and test procedures referenced for track terminology (Agricultural tractors - Test procedures).
• ISO 4004 was developed by ISO/TC 23 (Tractors and machinery for agriculture and forestry).

Keywords: ISO 4004, track widths, agricultural tractors, tractor track width, row‑crop machinery, wheel track, ISO standard.