Because the steer axle is used to steer a bus or truck, it is essential for tyres to have good steering properties. Steering must take place smoothly. Steering axle tyres are directional to keep a vehicle in the right direction – this requires a different tread pattern to a drive axle traction tyre. 

Here is a 10-point policy that complies with and is in addition to Regulation 212 of the National Road Traffic

1. Records of date fitted, brand, and all specifications of each tyre fitted to a vehicle, including the
position fitted and by whom, should be mandatory.

2. Only fit original equipment tyres (OEM) on a steering axle – recaps or grooving are strictly forbidden.

3. FREE Rolling Tyres (FRT) tyres are not permitted on a steer axle – FRT tyres are for trailer application
only – NOTE FRT tyres are denoted FRT on the side wall.

4. Steering axle tyres must displace water – tread depth should not be less than 4mm across the entire
tread pattern. 3mm is the absolute minimum pull point (extract from steering service). To be legal
the tread may not be level with the tread depth indicator. It would be advisable to change the
steering axle tyres before they get down to a 3mm tread depth, preferably at 5mm for safety reasons.

5. Steering tyre pressures must be measured on cold tyres – bleeding a hot tyre is forbidden – a loaded
hot tyre will gain as much as 20% kPa on a hot day.

6. Tyre pressure reading and pressure adjustment will not be left at sole discretion in the hands of a
pump jockey (Petrol pump attendant) – the driver is responsible/accountable for accurate pressures
and the driver must be aware (Educated / Trained on this issue) of significant tyre pressure
differentials and possible reasons for a pressure differential, especially when tyres are being checked
and inflated.

7. Valve caps must always be fitted – steel caps preferred. The valve stalk must not be under stress such
as bent sideways or damaged. All valves, especially on inner dual tyres, must be accessible.

8. A tyre pressure test should be conducted every 24 hours if possible or as close to that time frame as
possible – especially on long haul. Pressures should be recorded to identify the development of a slow

9. There is a tendency to load a truck against the headboard – the result is overloading the front axle and
steering axle tyres – be aware of correct load mass distribution.

10. At every long-distance stop the driver should conduct a quick walk-around inspection of all tyres with

a focus on the steering axle for the following:

a. Valve caps are present.

b. Touch test – tyres warm up in service but a tyre that is seriously under-pressured develops
excess heat and will be very hot in relation to other tyres on the vehicle.

c. No stones or objects jammed into the tread pattern.

d. No visible sidewall cuts, bulges, or unusual deformation of the tread belt