If you enter your registration into our site and you find that the results that come back include with two sizes, not one, you've likely got a staggered tyre setup.
Staggered tyres are simply front and rear tyres on a car with different sizes. Usually, this is with wider tyres on the back.
In many cases for rear-wheel-drive performance cars - and plenty of premium saloons - it changes how you buy, check and replace the tyres on your vehicle.
Below we explain why manufacturers do it and what it means for wear and rotation.
How do I know if my car has staggered tyres?
The quickest way to check is the current set up. The first port of call is to have a look at the tyre sidewalls. Every tyre has its size printed on it. You'll notice quickly that a staggered car has front and rear numbers that don't match.
A typical pairing might look something like this:
| Position
| Example size
| What's different
|
|---|
| Front
| 225/45 R18 | Narrower tread
|
| Rear
| 255/40 R18 | 30mm wider, lower profile
|
Please note: those figures are purely an example, not a recommendation for any particular car.
When reading the numbers, the first number is the tyre's width in millimetres. The second is the sidewall height as a percentage of that width. Quite often the rim size stays the same front and rear. However, that is not a fixed rule. Cars also run a larger wheel on the back, such as 19-inch fronts with 20-inch rears.
A good way to find the approved sizes in your owner's manual and on the tyre placard. This is usually on the driver's door or inside the fuel flap.
Also if you were to
search by registration on Blackcircles a staggered tyre set up will show as separate front and rear sizes.
Why do some cars have wider tyres on the back?
It mostly comes down to where the power comes from. On a rear-wheel-drive, the back tyres have to deal the most with the engine's power - and how that transfers onto the road.
A wider tyre has a larger contact patch. So more rubber on the tarmac gives the rear more traction when you are pulling away or need to accelerate out of a bend.
The narrower front tyres help in a different way. They keep the steering light and precise. Car manufacturers use the difference in grip between the two axles to control how the car behaves when you are at the limit.
We all want a car that stays stable at the back and is predictable when pushed. The tyre sizes are part of how an engineers ensures this outcome.
There is also an aesthetic angle for some. A fat rear tyre filling the arch is part of the appeal on sports cars. You'll find staggered setups from the factory on many BMW, Mercedes-Benz, Porsche, Jaguar and Ford Mustang models. As well as plenty of others.
Can you rotate staggered tyres?
No, not front to rear. Swapping tyres between axles can be a way to even out wear. However, a 255 rear won't go on a wheel and arch built for a 225 front. Also, the car's handling is set up around each size being in place.
Michelin's tyre rotation advice covers which patterns can go where. If you're unsure, ask your fitter before anything is moved.
Why rear tyres often wear out first
Without rotation, each axle wears at its own pace. On a powerful rear-wheel-drive car the rear tyres can wear down quicker - due to the pressure that they are put under from the driving forces.
It's worth noting too that it can also depend heavily on the car, the power and how you drive it.
Look at the tread on the fronts and the rears on their own rather than assuming all four are in the same state. The legal minimum is 1.6mm across the central three-quarters of the tread, around the whole tyre, and the rears can reach it well before the fronts.
Replacing in pairs
Because front and rear sizes differ, you'll usually be buying two tyres at a time rather than four.
It is recommended that you keep the pair on each axle the same make, model and size. Michelin's
guidance on mixing tyres says tyres on the same axle should be the same model. And our help centre explains
what the law says about different tyres on your car.
It's also worth staying with the same tyre range front and rear where you can.
Buying tyres for a staggered car
Getting the order right is mostly about reading the details carefully.
- Check both sizes. Confirm the front and rear sizes from the sidewalls or your handbook before you order, including the load index and speed rating on each.
- Look for manufacturer markings. Many cars with staggered setups leave the factory on tyres developed with the carmaker, marked on the sidewall. Porsche uses N-codes (N0, N1, N2 and so on), BMW uses a star, Mercedes-Benz uses MO and Audi uses AO.
- Check for run-flats. Some staggered cars, particularly BMWs, are fitted with run-flat tyres from new and may not carry a spare. Swapping to standard tyres is a bigger decision than it looks, so check with us or your fitter first.
Porsche is the strictest on matching. Its
dealer guidance says only tyres with the same make and the same N-specification code should be fitted. Also, cars with different front and rear sizes the brand, tyre name and N-spec should match front to rear (Hennessy Porsche).
What the law says
The rule on mixing tyres is in
regulation 26 of the Road Vehicles (Construction and Use) Regulations 1986.
It's about tyre structure rather than size: radial and cross-ply tyres, for example, mustn't be mixed on the same axle.
Different sizes front and rear are fine where the car was designed for them.
Different sizes on the same axle are not something we'd ever recommend, and the tyres on each axle need to be the right size and type for the car and in good condition, with at least 1.6mm of tread.
Finding the right tyres for each axle
If your rears are getting low while the fronts still look fine, that's normal on a staggered car.
Enter your registration on Blackcircles to see the correct front and rear sizes, then book fitting at a local garage or with a mobile fitter.
Frequently Asked Questions
Is it legal to have different size tyres front and rear?
Yes, as long as your car was designed for them and each tyre is the correct size and type for its position. The legal rules on mixing tyres are about structure, such as radial and cross-ply, on the same axle.
Can I put the same size tyre on all four wheels instead?
Only if the carmaker lists an alternative square fitment for your model. Fitting sizes the car wasn't designed for can affect handling, stability systems and clearance, so check your handbook or ask us first.
Do I have to replace all four tyres on a staggered car?
No. Most people replace one axle at a time, as each pair wears out. Keep both tyres on an axle the same make, model and size.
Why are my rear tyres wearing faster than the fronts?
On a rear-wheel-drive car the rears put the power down, so they usually wear quicker. Without front-to-rear rotation, that difference builds up over time. Uneven wear across a single tyre is different and may point to alignment or pressure problems.
Can I rotate tyres on a staggered setup?
Not front to rear, because the sizes are different. Side-to-side swaps may be possible if the tyres aren't directional, so check with your fitter.
What does N0 or a star mean on my tyre?
These are carmaker approval markings. N-codes are Porsche's, and the star is BMW's. They show the tyre was developed or approved for that manufacturer's cars, and matching them when you replace is a good idea.
