Pressure guidance and load ratings

Your tyre status lives in the Garage tab: open the vehicle or trailer and look at the Tyres section, which also feeds the Health grade. Pressure advice and load-rating checks answer two different questions, and it helps to keep them apart. loadmate can tell you whether the tyres on an asset have enough rated capacity for the load you have entered. It does not pretend to know the exact cold pressure your tyres need on a given day. For pressure, use the manufacturer placard (the sticker inside the driver’s door or by the fuel cap), the tyre sidewall, a tyre fitter, and your local road rules. Use loadmate to keep the load-rating and age picture visible as you load and plan.

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Use a trusted cold-pressure source

loadmate does not print one exact cold pressure for you, and that is on purpose. The right number depends on three things the app cannot read for you: how heavily you are loaded right now, the tyre maker’s own pressure-and-load table for that exact tyre, and your local road rules for heavily loaded towing. A single figure would have to pretend it knew all three, so loadmate leaves the pressure decision with the sources that genuinely hold it and keeps the load-rating and age picture in front of you instead. Set cold pressures from a source you trust:

• The manufacturer placard, usually inside the driver’s door frame or filler flap.
• The tyre sidewall, for the maximum cold pressure printed on it.
• A tyre fitter, who can advise for your loaded weight and how you tow.
• Your local road rules, which can set requirements for heavily loaded towing.

Set pressures when the tyres are cold, before driving warms them. As a conservative guide, running near the tyre’s maximum cold pressure suits a heavily loaded tow, but treat that as a starting point and confirm it against the placard or a fitter.

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Read the load index on the sidewall

The load index is the per-tyre weight rating printed on the sidewall. It sits just after the size code, as a number followed by a letter, for example 121S. That number is the load index, and the letter is the speed rating. The load index is the figure loadmate uses for the carrying-capacity check, so it is worth reading it off correctly when you set up the asset’s tyre profile. The sidewall shows it next to the size, and the tyre profile form has an inline tip pointing to where the number sits if you are not sure which figure to read. You enter it once, and from then on loadmate keeps the load-rating picture current for you. For more on entering and saving these values, see Set up your tyre profile.

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How loadmate checks carrying capacity

loadmate works out how much weight your tyres are rated to carry and compares it with what the asset actually weighs loaded. The carrying capacity is the per-tyre load-index rating multiplied by the number of tyres on the asset. So a set of four tyres each rated for a given weight gives a combined figure, and that figure is what your loaded weight is measured against. The loaded weight comes from the same numbers you already keep in loadmate. For a vehicle it is the loaded vehicle weight, and for a hitched trailer or caravan it is the loaded trailer weight. When that loaded weight comes within about ten percent of the combined tyre rating, loadmate flags it as marginal. When it goes over, loadmate flags it as exceeded. This is a gap that the usual towing limits miss: a rig can sit inside its vehicle and trailer ratings and still be over what the tyres are rated to carry, and you would not see it from the other compliance numbers. If there are no active loads on the asset yet, loadmate hides the carrying-capacity result rather than showing a figure against zero weight. Add your loads first, then the check has something real to measure against. To keep the loaded weight honest, keep your water, fuel, and gear current; see Water and consumables. Saving tyre details requires Pro.

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What age and region change

Tyres age from the day the rubber is made, not just from how far they have rolled, so loadmate also watches tyre age. It uses the manufacturing date from the sidewall DOT code when you have entered it, and otherwise falls back to the fitted date. As the tyres get older, loadmate first raises a warning to prompt a sidewall inspection, then a stronger alert when they are due for replacement regardless of tread. The age warnings are region-aware and trailer-aware. In Australia, loadmate raises an inspect-the-sidewalls warning from around four years and a replace-them alert from around five years. In the UK, Europe, and the US the warning starts from around five years and the replace alert from around six. Trailer and caravan tyres are flagged about a year sooner than those figures, because they often age in the sun and cover little distance even when the tread still looks fine. When loadmate raises an age warning or alert, treat it as a prompt to inspect the sidewalls and ask a tyre fitter before the next trip. For where these dates come from and how to read the sidewall code, see Set up your tyre profile. Terminology and units follow your region too. On Australian and UK pages tyres are spelled tyre and pressures read kPa first. On United States pages it is tire and PSI first. The combined tyre rating and loaded weight read in the unit system you have set, so the numbers match the figures you already work with.

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When to ask a tyre fitter

loadmate keeps the load-rating and age picture in front of you, but a fitter is the right call for anything you cannot settle from the placard and sidewall. Book a fitter or get tyres inspected when:

• You are unsure what cold pressure to run for how you load and tow.
• A tyre keeps losing pressure between trips.
• There is visible damage, a bulge, a cut, or uneven wear.
• loadmate raises an age warning or alert on the tyres.
• The carrying-capacity check comes back marginal or exceeded, and you cannot reduce the load.

A marginal or exceeded result means the tyres are at or over their rated capacity for the load you have entered. Either take weight off the asset or fit tyres with a higher load rating before you travel. If the result still looks wrong after that, recheck the load index and tyre count on the profile, since a mistyped number is the most common cause.