Vehicle guide
How do I find the correct tyre size and pressure?
Read the fitted tyre size from each sidewall, but obtain the recommended cold pressures from the vehicle handbook or manufacturer’s pressure label. Use the figures for the fitted wheel and tyre specification and the load being carried—not a generic pressure or the maximum shown on the tyre.
Match the tyres, pressure and load
9-second silent explainer · press play
Read the three steps
- 01 · SidewallRead every sidewall
Compare size, construction, load index and speed rating.
- 02 · PressureUse the vehicle's figures
Set cold pressures for the fitted tyres and current load.
- 03 · ConditionInspect tread and damage
Check wear, cuts, bulges and repeated pressure loss.
Tyre size, load rating and pressure affect handling, braking, wear and legal roadworthiness. The correct pressure belongs to the vehicle and its load, so a generic figure or sidewall maximum is not a substitute.
Find the vehicle-specific specification
- 1
Check the handbook and manufacturer’s pressure label, commonly found in a door shut, fuel flap or glovebox.
- 2
Select the pressure figures for the fitted wheel and tyre size and the current passenger or load condition.
- 3
If the handbook, pressure label and fitted tyres disagree, confirm the specification with the manufacturer or a qualified tyre professional.
- 4
Do not assume that another derivative, wheel size, van payload or towing setup uses the same pressures.
Read and compare every tyre
- 1
Read the width, aspect ratio, construction, rim diameter, load index and speed rating from each fitted tyre.
- 2
Check that tyres on the same axle are a compatible size and construction and are suitable for the vehicle and axle load.
- 3
Check directional arrows, inside or outside markings and whether specialist run-flat, reinforced, winter or all-season tyres have been fitted appropriately.
- 4
Include the spare tyre where one is supplied, or confirm that the repair kit, compressor and locking-wheel-nut key are present and usable.
Inspect tread and condition
- 1
For cars, light vans and light trailers, tread must be at least 1.6mm across the central three-quarters of the breadth and around the full circumference.
- 2
Check for cuts, bulges, exposed cords, cracking, embedded objects and damage to the tread or sidewall.
- 3
Use date markings as condition and manufacturer-guidance evidence rather than assuming tyre age alone makes a tyre illegal.
- 4
Cuts exposing cord, bulges, seriously low pressure or another unsafe defect require professional assessment before driving.
Set and monitor pressures safely
- 1
Measure and adjust pressures when the tyres are cold, following the manufacturer’s instructions and using a reliable gauge; do not bleed a warm tyre down to a cold-pressure figure.
- 2
Set each tyre to the specified pressure for the current load, then refit the valve caps.
- 3
Reset the tyre-pressure monitoring system only after correcting the pressures and following the vehicle handbook.
- 4
Recheck after a substantial load change and investigate repeated warnings, pressure loss or abnormal wear rather than repeatedly resetting the system.
Your practical checklist
Tick each item as you work through the vehicle, documents and evidence. An unticked item stays open—it does not become a clear result.
Useful sources and next steps
Questions buyers ask
Is the pressure printed on the tyre correct for my vehicle?
Not necessarily. A sidewall figure can be a tyre limit rather than the vehicle manufacturer’s recommendation. Use the handbook or vehicle-specific pressure label.
Should tyre pressures be checked hot or cold?
Use the manufacturer’s instructions; normal guidance is to check before the journey when tyres are cold because heat changes the reading.
What is the legal tread depth for a car or light van?
At least 1.6mm across the central three-quarters of the tread breadth and around the full circumference. A tyre can still be unsafe because of damage or defects even where tread depth is above the minimum.
Can different tyre makes be fitted on one axle?
Brand alone is not the complete test. Check size, construction, load and speed suitability, directional or asymmetric fitting and the vehicle manufacturer’s requirements. Ask a qualified tyre professional where the combination is unclear.
Should I reset the TPMS when its warning appears?
First check and correct every tyre pressure and inspect for damage or leakage. Reset the system only as directed by the handbook; do not use a reset to conceal a recurring warning.
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