Tyre Pressures for Towing a Caravan: The Complete Guide
Hitching up a caravan adds hundreds of kilograms to your rig and shifts weight onto the rear axle through the towball. That extra load changes the correct tyre pressure for both the tow vehicle and the van itself. Get it wrong and you risk sway, overheating, uneven wear and, in the worst case, a blowout at highway speed with a heavy trailer behind you. This guide covers both vehicles, gives you a simple weight-based method, and keeps every figure as a guide because the right numbers depend on your specific rig, its weights and its tyres.
What tyre pressure should your tow vehicle run when towing?
Most vehicle tyre placards list two pressures: a normal figure and a higher one for full load or high-speed/towing use. When you hitch up a van, you are loading the vehicle heavily and adding towball download to the rear, so you should move to that higher laden column — often 4–8 psi more, especially on the rear axle. If your placard doesn’t show a separate towing column, follow the “maximum load” figure and confirm with your handbook.
Running the normal, unladen pressure while towing lets the tyres flex too much under the extra weight. That builds heat, wears the shoulders, and raises the risk of failure. The fix is simple: use the load-rated column, set it cold, and check it before you leave. For the fully loaded family wagon without a van, the same principle applies — see pressures for a fully loaded family road trip. And remember the tow vehicle’s tyres must still meet the vehicle’s placard load rating in the first place.
How do you calculate the right pressure for caravan tyres?
A caravan’s tyres should be inflated for the weight they actually carry, not simply pumped to the sidewall maximum. A widely used Australian method works from your van’s real axle weight:
- Weigh your loaded van to find its GTM (Gross Trailer Mass — the weight on the van’s own axles, hitched and loaded).
- Work out the load per tyre: for a single-axle van, that’s roughly half the GTM; for a twin-axle (dual-axle) van, roughly a quarter.
- Apply the formula: divide the tyre’s maximum pressure by its maximum load (from the load index), then multiply by the actual load on that tyre.
A worked example from Australian caravan guidance: a single-axle van at 1200 kg GTM on a 205/65R15 94H tyre (max load 670 kg, max 60 psi) works out to about 54 psi. The same tyre on a 1800 kg twin-axle van carries less per tyre and works out to about 41 psi. These are illustrative — your figures depend entirely on your van’s real weight and tyre rating.
| Rig | What sets the pressure | Guide |
|---|---|---|
| Tow vehicle | Placard laden/full-load column | Normal + ~4–8 psi (esp. rear) |
| Caravan (single-axle) | ~½ GTM per tyre vs tyre max load/pressure | Often higher; e.g. ~54 psi in the example |
| Caravan (twin-axle) | ~¼ GTM per tyre vs tyre max load/pressure | Lower per tyre; e.g. ~41 psi in the example |
If maths on the roadside isn’t your thing, many Australian caravan retailers and clubs publish free online tyre-pressure calculators that use the same weight-based approach. The key input is an accurate loaded weight — guessing high and running the sidewall maximum gives a harsh ride, centre wear and less grip.
Why does towing need higher pressures?
More weight on a tyre means more flex in the sidewall as it rolls. Flex generates heat, and heat is what destroys tyres — it is the root cause of most highway blowouts on loaded rigs. Correctly higher pressure stiffens the tyre so it carries the load with less flex, runs cooler, steers more precisely and resists sway. Under-inflating a loaded tow tyre is one of the most dangerous mistakes a caravanner can make; see what happens if you underinflate your tyres.
Do caravan tyre pressures change when hot?
Yes, and that’s normal. A hot caravan tyre typically reads about 4 psi higher than when cold — the basis of the widely used four-pounds rule. Always set your target pressures cold, first thing before you drive. Don’t bleed air out of a hot tyre to hit the cold number — you’ll be badly under-inflated once it cools. In an Australian summer, heat plus a long highway haul can push readings up noticeably; that rise is expected and not a reason to let air out.
What else should you check before towing?
Caravan tyres often age out before they wear out, because vans sit unused for long stretches. Check the DOT date code and inspect for cracking — many touring guides suggest replacing van tyres by around five to six years regardless of tread. Don’t forget the van’s spare (and the tow vehicle’s). Confirm your rig sits within its GVM, ATM and GCM limits; those weight ratings are a legal and safety matter beyond pressure, covered in tyre rules for towing. For long hot hauls, see best tyres for towing a caravan across the Nullarbor.
Bottom line: Set the tow vehicle to its laden placard column and the van from its real axle weight — both need more air than an empty car. Inflate cold, expect a ~4 psi rise when hot (don’t bleed it off), and check the van’s tyre age and spare before every trip.
Frequently asked questions
What tyre pressure should I run when towing a caravan?
Run your tow vehicle at its higher laden/full-load placard column (often 4–8 psi above normal, especially the rear). Set the caravan’s tyres from its actual loaded axle weight against the tyre’s max load and pressure. All figures are a guide — confirm with your placard and tyre maker.
Should caravan tyres be at the maximum pressure on the sidewall?
Not automatically. The sidewall figure is the tyre’s maximum, not a target. Inflate for the weight the tyre actually carries. Running the maximum on a lightly loaded van gives a harsh ride, centre wear and less grip.
Do I increase tow vehicle tyre pressure for the towball weight?
Yes. Towball download loads the rear axle, so moving to the laden column (higher rear pressure) helps the vehicle carry it, reduces sway and runs cooler. Follow your placard’s full-load figures and your handbook.
Should I set caravan tyre pressures hot or cold?
Cold, before you drive. A hot van tyre reads about 4 psi higher — that’s normal. Never let air out of a hot tyre to reach the cold target, or you’ll be under-inflated once it cools.
How old is too old for caravan tyres?
Vans often age out before they wear out. Check the DOT date code and look for cracking; many touring guides suggest replacing van tyres by around 5–6 years regardless of tread. Confirm with your tyre maker.
Figures in this article are a 2026 guide only. Correct pressures depend on your specific vehicle, van, loaded weights and tyres — always confirm with your vehicle placard, the tyre manufacturer, and weigh your loaded rig.
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