255/40 R18 Tyres in Park Royal
255 mm wide, 40% profile, for an 18-inch wheel. Fitted at our NW10 workshop, with live prices online.
255/40 R18 is an 18-inch tyre, 255 mm wide, with a sidewall 102 mm tall (40% of the width). We fit 255/40 R18 tyres at our Park Royal garage in NW10, with balancing, a new valve and disposal of the old tyre included. The price depends on the brand: see live prices for 255/40 R18. It is fitted to cars such as the BMW 3 Series and BMW 4 Series.
What 255/40 R18 means
- 255: the tyre is 255 mm wide, measured across the sidewalls.
- 40: the sidewall height is 40% of the width, so 255 × 40% = 102 mm.
- R: radial construction. A ZR in the same place is the same size with a speed marking for over 240 km/h.
- 18: it fits an 18-inch wheel. Overall diameter is 18 × 25.4 mm plus two sidewalls: 661.2 mm.
The load index and speed rating follow the size on the sidewall (for example 91V). Replace like for like or higher, as your handbook states.
Cars that use 255/40 R18
Manufacturer and tyre-maker fitment listings give 255/40 R18 for these models, usually as one of several wheel options. The size on your own tyres, or on the placard in the door frame, is the one to match.
| Make | Model | Generation |
|---|---|---|
| BMW | 3 Series | F30 saloon, facelift (2015-2019) |
| BMW | 3 Series | G20 saloon (2019-, including 2022 facelift) |
| BMW | 4 Series | F32 Coupe, facelift (2017-2020) |
| BMW | 4 Series | G22 Coupe (2020-2024) |
What to look for in a 255/40 R18 tyre
- Low profile, less cushion. A 102 mm sidewall on an 18-inch wheel leaves little to absorb a pothole or a kerb, so check for bulges and rim damage after a hard hit, and have the wheel alignment checked if the steering pulls or the new tyres wear on one edge.
- Winter or all-season. If you want winter or all-season tyres in 255/40 R18, the live list shows what is made in this size today; not every pattern is made in every size.
255/40 R18 tyres by price band
These are the brands we fit, by price band. Which of them make 255/40 R18, and at what price today, is on the live price list.
- Premium: Continental, Pirelli, Hankook, Yokohama, Bridgestone, Dunlop, Goodyear, Michelin
- Mid-range: Avon, Nankang, Roadstone, Kumho
- Budget: Accelera, Linglong
Prices for 255/40 R18 depend on the brand — see live fitted prices for 255/40 R18.
Book online, call 020 3886 2355 or WhatsApp 07476 586 589. We fit at Unit 4 Unimix House, Abbey Road, Park Royal, London, NW10 7TR, balancing and a new valve included.
Sizes next to 255/40 R18
Same 18-inch rim, one step wider, narrower, taller or lower.
Sizes with a similar overall diameter
These sizes are within 3% of the 661.2 mm diameter of 255/40 R18 on paper, and within 20 mm of its width. That alone does not make them approved for your car: check the handbook or the door placard, and keep one size across an axle.
| Size | Overall diameter | Difference |
|---|---|---|
| 255/35 R19 | 661.1 mm | -0.0% |
| 265/35 R19 | 668.1 mm | +1.0% |
| 235/45 R18 | 668.7 mm | +1.1% |
| 245/45 R17 | 652.3 mm | -1.4% |
| 275/35 R18 | 649.7 mm | -1.7% |
| 275/35 R19 | 675.1 mm | +2.1% |
See all tyre sizes, or read how our tyre fitting works.
Frequently asked questions
Is 255/40 R18 the same as 255/40 ZR18?
Yes, the dimensions are the same. The Z marks a tyre rated for over 240 km/h (149 mph); the exact rating is the letter after the load index, such as W or Y. Fit at least the speed rating your handbook gives for the car.
Can I fit 255/35 R19 instead of 255/40 R18?
Only if 255/35 R19 is listed for your car. On paper it is 661.1 mm tall against 661.2 mm for 255/40 R18, a 0.0% difference, so the speedometer would barely change. It also needs a 19-inch wheel instead of an 18-inch one. Wheel width, arch clearance, load index and speed rating must suit the car too, so check the handbook or the door placard, and fit one size across an axle.
How tall is a 255/40 R18 tyre?
About 661.2 mm (26.0 inches) across when new and unloaded: the 18-inch rim (457.2 mm) plus two sidewalls of 102 mm, which is 40% of the 255 mm width. Real tyres differ by a few millimetres between brands and patterns.
Which cars use 255/40 R18 tyres?
Fitment listings give 255/40 R18 for the BMW 3 Series and BMW 4 Series. One model can use several sizes depending on its wheels, so check the sidewall of your own tyres before you book.
Same-Day Tyre Fitting & Walk-Ins Welcome
New tyres fitted while you wait, plus puncture repairs, wheel balancing and battery replacement at our Park Royal workshop. No appointment needed for tyres, just call in.