Ifor Williams HB506
Tyre pressures and wheel nut / bolt torque
Tyre specification
Fitment details
- For the P0841 165R13C 8PR assembly on the four-fixing steel wheel.
- This does not establish the torque for optional alloy wheels.
Tyre pressure placard
Ifor Williams HB506 trailer visual reference.
| Tyre size | kPa | PSI | bar |
|---|---|---|---|
| 165R13C | 450 | 65 | 4.5 |
Please ensure the maximum pressure marked on your tyre sidewall is equal to or higher than the pressure listed here.
A tyre of the same size with a lower pressure rating may have been fitted by mistake.
Never exceed the maximum pressure marked on the tyre.
Is your tyre load rating high enough?
Find the load index beside the tyre size. For example, 104 = 900 kg per tyre. For normal trailer wheels, use the first number in 104/102N. The second is for tyres mounted side by side on one hub, not a trailer with two axles. N is the speed symbol.
Open the tyre load rating conversion chart →
Capacity per tyre × number of road tyres = combined tyre capacity. Do not count the spare or jockey wheel.
Example: four tyres rated 104 give 900 × 4 = 3,600 kg, which exceeds a 3,500 kg trailer maximum gross weight by 100 kg. This is a total-capacity comparison only.
Check your tyre capacity
Enter all three values to compare capacity.
Check every axle too: its tyres must support its plated maximum axle weight, and no individual tyre may be overloaded. This calculator assumes all tyres have the same load index and are mounted singly. It does not confirm fitment or set tyre pressure. Keep the trailer manufacturer’s required load and speed ratings, use the specified cold pressure and check the actual loaded axle weights.
Cold tyre pressure
65 PSI / 4.5 bar / 450 kPa
A separate unloaded or fully laden pressure has not been confirmed for this entry.
Wheel nut / bolt torque
Use the setting only for the wheel and fixing specification described above.
Frequently asked questions
What is the tyre pressure for the Ifor Williams HB506 horsebox trailer with 165R13C tyres?
The tyre pressure for the Ifor Williams HB506 horsebox trailer with 165R13C tyres is 65 PSI (4.5 bar / 450 kPa), measured cold. This applies to the specified P0841 165R13C 8PR wheel assembly. Lower-rated tyres are not covered.
What is the wheel nut or bolt torque for the Ifor Williams HB506 horsebox trailer?
The wheel nut or bolt torque for the Ifor Williams HB506 horsebox trailer is 88 Nm. This applies to the standard four-bolt steel wheel with M12 wheel bolts (normally a 19 mm socket). It does not establish optional alloy-wheel torque.