The paper aims to determine the permissible wheel load, wheel radius, and speed on a railroad considering fatigue shear stress in the rail head. In the literature, there are permissible wheel load and wheel radius formulae which consider shear fatigue limit as permissible shear stress; and hence do not offer acceptable wheel load, radius and speed. The deficiency lies in the permissible shear fatigue stress value. The permissible shear fatigue stress is suggested to be 24.4% of the tensile strength of rail steel with an assumed reliability of 99%. Addressing the deficiency, formulae are suggested for permissible wheel load, wheel radius and speed under three approaches. The formulae are generalised too considering the coefficient of friction at the wheel tread/rail interface. The permissible speed is suggested to be the minimum of two speeds based on the permissible shear fatigue stress at the wheel tread/rail interface and bending fatigue stress at the rail foot. A bending fatigue stress corresponding to a reliability of 95% is suggested for heavy haul because it makes a close balance between the two aforementioned speeds.