Tyre Pressure Guide
Check the compliance sticker — usually on the driver's door jamb, the glovebox, or the fuel filler flap. This is the manufacturer's figure and is not the same as the max pressure printed on the tyre sidewall.
Trailer tyres don't get a vehicle placard — the figure printed on the tyre sidewall is the tyre's maximum rated pressure. Most manufacturers recommend running close to that maximum when loaded, since trailer tyres carry a fixed load with no engine weight to offset it. Check your caravan's compliance plate and tyre manufacturer's data sheet to confirm.
A heavier load generally needs higher pressure, within the tyre's rated range. If you've used the Weight & Balance Visualiser and know you're running close to your GVM/ATM, it's worth checking with your tyre supplier whether your current pressure still suits that load.
Always check pressure when tyres are cold — first thing in the morning, or after the vehicle has been stationary for a few hours. Driving heats the tyre and air inside it, which raises the reading. As a rough rule of thumb, pressure rises by around 1 PSI for every 5–6°C rise in tyre temperature.
Don't "correct" a hot reading by letting air out to match your cold target — that will leave you underinflated once the tyre cools back down.
Extra tyres you add here (like a spare) won't appear on the diagram above, but are tracked the same way in the log below.