Complete Guide to Safe and Stylish Car Tire Upsizing

Changing car tires from the standard size to larger ones, or what is often called upsizing, is no longer just a trend to make the vehicle look more stylish. Many drivers upsize their tires to improve performance and increase comfort. However, this step should not be taken carelessly. Without proper calculation, changing tire sizes can actually reduce comfort and compromise driving safety.

Therefore, before changing your car’s tire size, it’s a good idea to read Dunlop’s complete guide to tire upsizing.

What Is Tire Upsizing?

In simple terms, tire upsizing means replacing car tires with a larger size than the factory standard. This is usually done to give the car a sportier look, add stability when cornering, adjust aftermarket rims, or increase ground clearance for SUVs.

Risks of Incorrect Tire Upsizing

• Inaccurate speedometer
  If the tire diameter is larger than standard, the speedometer will show a lower speed than the actual one. This can be dangerous, especially on highways or when passing through electronic ticketing areas.
• Handling and suspension disruption
  Larger or heavier tires can burden the suspension. As a result, the car may feel stiffer or unstable, the turning radius narrower, and the tires may rub against the fenders or suspension components.
• Increased fuel consumption
  The added width and weight of the tires put extra load on the engine, making fuel consumption less efficient.
• Faster tire wear
  If tire pressure does not match due to incorrect sizing, uneven wear can occur and shorten tire lifespan.

Another common question: is it possible to change tire size without changing rims? The answer is yes, as long as the total tire diameter does not change more than ±3% from standard. This method is often called “tire-only upsizing” and is generally safer.

What Should Be Considered When Upsizing Car Tires?

1. Choose the right tire size (Use a Tire Size Calculator)
   The main factor in choosing tire size is keeping the overall diameter stable, ideally not changing more than ±3% from the standard size. Why is this important? Because diameter changes affect speedometer accuracy, handling, comfort, and clearance between the tire and fender.
   Instead of manual calculation, the easiest and most accurate way is to use a free Tire Size Calculator such as on tiresize.com or wheel-size.com.
   Steps:
   • Click the Tire Size Calculator menu.
   • Enter the tire size you are currently using.
   • Enter your car’s standard tire size.
   • Click Calculate to see the results.
   • Check the Alternate Tire Size table. If you want a larger tire, click on the size with a bigger inch measurement.
   • Choose the size with the smallest percentage difference (recommended in green).
2. Pay attention to clearance and suspension
   Upsizing is not just about numbers. Make sure there is enough space in the brake, fender, and suspension areas so the tires do not rub when maneuvering or driving on bumpy roads. Consulting an experienced mechanic is highly recommended.
3. Understand legal and regulatory aspects
   Modifications that do not change the technical specifications or the original shape of the vehicle can be done, but if there are changes to the shape, dimensions, or other specifications, it must be reported and approved by the authorities through a type test.
   Make sure the modifications you make do not affect your safety or the comfort of other road users. For example, in rim modification, avoid rims with sizes that are too large and interfere with the braking system or vehicle maneuverability.
   Legal Basis for Vehicle Modification:
   • Law Number 22 of 2009 on Road Traffic and Transportation.
   • Government Regulation Number 55 of 2012 on Vehicles.
4. Always consider rim width and offset
   Rims that are too wide or have unsuitable offsets can cause rubbing with the fender or suspension components.
   What is offset? Offset is the distance between the centerline of the rim and the hub mounting surface. Positive offset means the hub surface is closer to the outer rim, while negative offset means it is closer to the inner rim. Offset changes affect wheel position in the fender and may impact handling and cause rubbing.
   Since every inch of the rim and tire aspect ratio affects total diameter, balance is key. Too large makes the car prone to slipping when cornering, too small reduces stability and handling response.
5. Choose quality tires with proven performance
   Choosing the right tire is the most important step in upsizing. Make sure the tires come from trusted brands with tested performance and quality, such as Dunlop and Falken.
   Dunlop is known as a premium tire manufacturer prioritizing safety, comfort, and performance. Falken, as Dunlop’s sister brand, offers a wide line-up of modern tires with sporty designs, ideal for upsizing needs for daily use or performance-oriented drivers.

Recommended Products for Upsizing

• Falken ZIEX ZE310R Ecorun

  • Offers a balance of grip and comfort.
  • Designed for high stability and maximum grip in both wet and dry conditions.
  • Uses Advanced 4D Nano Design Technology for optimal grip and longer tire life.
  • Suitable for sedans and hatchbacks seeking sporty looks with daily comfort.
  • Available sizes: 15–20 inches.

• Dunlop SP Sport LM705

• 
  • Designed to provide comfort even with different sizes from standard.
  • With an asymmetric tread pattern and Noise Reduction Technology, LM705 offers a balance of grip and comfort.
  • Available sizes: 15–18 inches.
  • Suitable for: sedans, MPVs, and daily SUVs.

If you are unsure about selecting tire sizes or types, it is best to consult directly with an official Dunlop Shop or Falken Shop dealer. In addition to technical advice, you can also ensure installation is carried out safely.

Conclusion

Tire upsizing can indeed make cars look more stylish and improve performance in certain conditions. However, never forget the main principle: size changes must be done with accurate calculation so they do not negatively affect driving comfort and safety.

Use a tire size calculator, pay attention to technical and legal aspects, and choose tires from trusted manufacturers like Dunlop, which offers a wide range of sizes for your needs. 

Reference:

1. https://otomotif.kompas.com/read/2025/03/01/112200715/tips-aman-ganti-ukuran-ban-mobil-tanpa-mengurangi-keamanan
2. https://otomotif.bisnis.com/read/20230109/46/1616231/kenali-aturan-modifikasi-mobil-agar-aman-dan-bebas-tilang
3. https://www.hukumonline.com/berita/a/ketahui-modifikasi-mobil-yang-tak-melanggar-hukum-lt628c932b5c5ca/
4. https://peraturan.bpk.go.id/Details/38654/uu-no-22-tahun-2009