How often should you check tire pressure, rotate and replace tires? Pressure, tread and age

Tire pressure: monthly, and always cold

Check every tire, including the spare, at least once a month and before any long trip. Michelin notes that tires can lose up to 1 psi a month, and Kia’s owner’s manual asks for the same monthly check. The UK Highway Code goes further and says to check weekly, before your journey.

How to do it:

1. Measure cold: before you’ve driven, or at least three hours after, Michelin says. The Highway Code warns that warm tires can give a misleading reading.
2. Use the right number: the recommended pressure is on the sticker in the driver’s door jamb or glove box, and in your owner’s manual. Don’t use the number on the sidewall — that’s the tire’s maximum, not your car’s recommendation.
3. Add air or let some out until each tire matches that number.

It pays off. fueleconomy.gov estimates that keeping tires at the right pressure improves gas mileage by 0.6% on average and up to 3%, and that mileage drops about 0.2% for every 1 psi the average pressure falls. Properly inflated tires are also safer and last longer.

A tire pressure monitor isn’t a replacement. Kia’s manual explains that the TPMS light only comes on when a tire is significantly under-inflated, and that it is no substitute for proper maintenance.

Scooter manuals ask for it even more often. KYMCO’s Agility manual says to check tire condition and pressure before each ride, and to adjust pressure only when the tires are cold.

Rotation: about every 6,000–8,000 miles

Rotate your tires about every 6,000–8,000 miles (roughly 10,000–13,000 km), or on your vehicle maker’s schedule. That’s Michelin’s general guideline; one current Kia manual says every 8,000 miles (13,000 km). Front and rear tires wear differently, and Michelin points out that skipped rotations leave uneven wear across all four, so the whole set needs replacing sooner.

The easy way to keep up is Michelin’s suggestion: book a rotation with every oil change, since the intervals are similar (see how often to change your car’s oil).

Replacement: tread, damage and age

Replace a tire when the tread reaches the wear bars, when the sidewall is damaged, or when it gets too old — whichever happens first.

Sign	What to look for
Tread	Wear bars molded into the grooves. When the tread is level with them — 2/32 inch (1.6 mm) — Michelin says the tire should be replaced.
Legal minimum (UK)	Cars: 1.6 mm across the central three-quarters of the tread. Motorcycles: 1 mm. Mopeds: visible tread.
Sidewall damage	Cuts, cracks, bulges or blisters. Michelin says sidewall damage can’t be repaired; have it inspected right away.
Age	Michelin: a thorough professional inspection every year after five years in service; replacement ten years after manufacture, spares included.

To find a tire’s age, read the last four digits of the DOT code on the sidewall: week, then year. Michelin’s example is 3520, the 35th week of 2020. Legal tread limits outside the UK vary, so check your own country’s or state’s rules.

Common mistakes

• Inflating to the sidewall number: that’s the maximum, not the recommendation.
• Checking right after a drive: warm tires read wrong; measure cold.
• Trusting the TPMS light alone: it only warns when pressure is already well down.
• Ignoring age because the tread looks fine: rubber ages from heat, sunlight and ozone even when you can’t see it.
• Forgetting the spare: it ages on the same clock as the others.

How to remember

A monthly check works best on a fixed day. Michelin suggests the first of every month. Track “check tire pressure” as a monthly item and set the reminder for a morning when you usually take the car out; give the tread and sidewalls a quick look at the same time.

Add tire rotation as its own item, set to however long it usually takes you to drive 6,000–8,000 miles, and note the odometer reading each time so you can tell when you’re close. When you buy new tires, note the DOT date and the odometer reading — that’s what you’ll need to work out the five- and ten-year marks. If there’s a scooter in the household, its tires get checked the same way, alongside its much more frequent oil changes (see how often to change scooter oil).