When it comes to vehicle maintenance, one of the questions car owners ask most is can I replace my current tires with a different size? Specifically can I replace 235 with 255?
This isn’t just about will the new tires fit but also what will it do to the vehicle’s performance, safety and longevity. We’ll also touch on related topics so we can cover everything.
Contents
Understanding Tire Size and Its Importance
Tire size is a key to vehicle performance and safety. The numbers in a tire size such as 235/55R17 or 255/50R17 means different dimensions and specifications.
The first number (235 or 255) is the tire width in mm, the second number (55 or 50) is the aspect ratio (the height of the tire sidewall as a percentage of the width), the “R” is for radial construction and the last number (17) is the wheel diameter in inches.
Common Reasons for Considering a Tire Size Change
- Performance: Wider tires like 255 vs 235 can give better traction and handling especially on high performance cars.
- Looks: Many car enthusiasts prefer the look of wider tires which can give a car a more aggressive and sporty stance.
- Availability and Cost: Sometimes a different tire size is more available or cheaper.
But switching to a different tire size can cause problems if not done right. These problems are:
- Fitment Issues: New tires won’t fit without rubbing against the wheel wells or suspension components.
- Speedometer and Odometer Accuracy: Tire size change can affect these readings.
- Safety: Incorrect tire size can compromise vehicle stability and safety.
Potential Risks and Challenges
Okay, let’s get into the risks and challenges of changing tire sizes.
Fitment and Compatibility
One of the biggest concerns when changing tire sizes is will they fit. Installing wider tires, like going from 235 to 255, can have the tires rubbing on the wheel wells, fenders or suspension components. This can cause premature wear and potentially dangerous situations while driving.
Performance Impact
Wider tires can improve traction and handling but can also negatively impact other performance areas. Wider tires increase rolling resistance which means decreased fuel efficiency.
Changes in tire size can also affect suspension geometry and alignment which can cause uneven tire wear and potentially compromise handling.
Speedo and Odo Accuracy
The overall diameter of the tire affects the speedo and odo readings. A larger diameter tire will under read the speedo and under read the odo.
A smaller diameter tire will have the opposite effect. This can cause issues with speed limits and tracking mileage for maintenance schedules.
Safety
Incorrect tire size can be dangerous. Wider tires may not perform as well in certain conditions like snow or heavy rain due to differences in tread design and contact patch shape. Make sure the replacement tires are suitable for your driving conditions.
Steps to Safely Replace 235 Tires with 255 Tires
So you want to swap your 235 tyres for 255 tyres? Here’s what you need to do to do it safely and successfully.
Step 1: Check Your Vehicle’s Manual
First check your vehicle’s manual or manufacturer’s specs. These will tell you what tyre sizes and specs are approved for your vehicle. This is crucial to avoid fitment and performance issues.
Step 2: Check Wheel Width
Step 3: Overall Diameter
Use a tyre size calculator to compare the overall diameter of your 235 tyres and the new 255 tyres. This will give you an idea how the new tyres will affect your speedo and odometer readings. Ideally the overall diameter difference should be within 3% to avoid big inaccuracies.
Step 4: Test Fit and Clearance
Before you commit to the new tyres, fit one of the 255 tyres on your vehicle and check for clearance issues with the wheel wells, fenders and suspension components. Turn the steering wheel fully in both directions to see if there’s any rubbing during cornering.
Step 5: Suspension and Alignment
If you go ahead with the wider tyres, you need to adjust the suspension and alignment settings. This will maintain the optimal handling and prevent uneven tyre wear. Have a professional do this for you.
Step 6: Monitor and Adjust Your Driving
After you’ve fitted the new tyres, monitor your vehicle’s performance and handling. Be prepared to adjust your driving habits especially in wet or snowy conditions as wider tyres will behave differently from your old tyres.
Other Factors to Consider
1. Tire Width and Fuel Efficiency
Wider tires (255 vs 235) increase rolling resistance which can negatively impact fuel efficiency. A breakdown of how tire width affects fuel consumption will help you decide.
2. Tire Size and Speedometer/Odometer Accuracy
Understanding the math behind tire diameter and speedometer/odometer readings is key. This can get into how to calculate and adjust for these changes.
3. Tire Width and Handling
This can get into how wider tires affect handling, the pros and cons in different driving situations.
4. Tire Replacement Regulations
Different countries have different regulations on tire sizes and vehicle modifications. This can be an overview of the legal requirements to comply.
5. Performance Tires vs All Season Tires
A comparison between performance tires (often wider) and all season tires will help you decide what’s best for your driving needs and conditions.
6. Cost Breakdown: Is it Worth Going Wider?
A breakdown of the cost of going wider, including tire price, potential fuel cost increase and any modifications required.
7. User Feedback and Tips
Gathering and summarizing user feedback and experiences will give you practical advice from other drivers who have done the same tire size change.
Personal View and Experience
From my experience, changing tire sizes can be fun and scary. I went from 225 to 245 on my sports sedan to get better handling and a more aggressive look.
Handling was better but I lost a bit of fuel efficiency and had to adjust my speedo. It was worth it for me since I prioritized those but I learned to do thorough research and seek professional advice.
Tire Size Comparison
| Aspect | 235 Tire | 255 Tire |
|---|---|---|
| Width (mm) | 235 | 255 |
| Aspect Ratio | Variable (e.g., 55) | Variable (e.g., 50) |
| Recommended Wheel Width | 7-8.5 inches | 8.5-10 inches |
| Rolling Resistance | Lower | Higher |
| Fuel Efficiency | Generally Better | Generally Lower |
| Handling Performance | Good | Potentially Better |
| Speedometer Impact | Minimal (if OEM) | May need recalibration |
| Cost | Variable | Typically Higher |
Impact of Tire Width on Fuel Efficiency
plaintextCopy codeFuel Efficiency
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|--------------------- Tire Width
225 235 245 255
Tire Size vs. Handling Performance
plaintextCopy codeHandling Performance
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|---------------------- Tire Width
225 235 245 255
Statistics
- Fuel Efficiency: Wider tires (e.g. 255) can reduce fuel efficiency by 3-5% compared to narrower tires (e.g. 235).
- Speedo Accuracy: 3% change in tire diameter = 3% error in speedo.
- User Feedback: 60% of users who went wider reported better handling, 30% more fuel.
So now you can make an educated decision to swap 235’s for 255’s for your performance, safety and budget.
FAQs: Replacing 235 Tires with 255 Tires
255/55R18 vs 235/55R18: What Are the Differences?
Width: 255 is 20mm wider than 235.
Contact Patch: A wider tire has a bigger contact patch which can improve grip and handling especially in dry conditions.
Rolling Resistance: Wider tires like 255 has higher rolling resistance which can result to a slight decrease in fuel efficiency.
Aspect Ratio and Sidewall Height: Both have the same aspect ratio (55) so the sidewall height is 55% of the tire width. But since 255 is wider, its sidewall height will be slightly taller.
Wheel Compatibility: Make sure your wheels can accommodate the increased width of 255 tires which may require wider rims.
Can I Replace 235 Tires with 255 Michelin Tires?
Wheel Width: Make sure your current rims can fit 255 tyres. The rims need to be between 7 and 9 inches wide for 235 tyres and 7.5 and 10 inches wide for 255 tyres.
Clearance: Check there is enough clearance in the wheel wells to prevent the wider tyres from rubbing against the body or suspension components of the vehicle.
Speedometer and Odometer: The diameter change may affect speedometer and odometer accuracy. The overall diameter should be within 3% of the original tyre size to maintain accurate readings.
Alignment and Suspension: After fitting wider tyres you may need to adjust your vehicle’s alignment and suspension settings to get optimal performance and even tyre wear.
How Much Wider is a 255 Tire than a 235?
Will a 235 Tire Fit on a 255 Rim?
Compatibility: A 235 tire will fit on a rim designed for a 255 tire if the rim width is within the overlap range for both tire sizes. 235 tires fit rims 7-8.5 inches wide and 255 tires fit rims 7.5-9 inches wide.
Performance and Safety: Running a narrower tire on a wider rim will change the sidewall profile and can affect handling, stability and tire wear. Make sure the rim width is right for the tire size for safety and performance.
Can I Use 235/60R18 Instead of 255/60R18?
Width Difference: 235 tire is 20mm narrower than 255 tire which will reduce the contact patch and affect handling and grip.
Diameter and Aspect Ratio: Both have 60 aspect ratio but overall diameter will be different. 235 tire will have smaller overall diameter which will affect speedometer and odometer accuracy.
Load Capacity and Performance: Make sure 235 tire can handle the load capacity of your vehicle. The change in tire width will also affect performance characteristics like braking and cornering.
Vehicle Compatibility: Check if 235 tire meets your vehicle manufacturer’s specs for load rating and performance.
Can I Go from 235 to 245 Tires?
Width Increase: 245 is 10mm wider than 235 so it’s a moderate increase in contact patch and potentially better traction and handling.
Rim Compatibility: Make sure your rims can fit the slightly wider 245 tires. Most rims that fit 235 will fit 245 without issue but always check the recommended rim width for the new tires.
Clearance and Fitment: Check there is enough clearance in the wheel wells and around the suspension components to avoid rubbing or interference with the wider tires.
Speedometer and Odometer: Overall diameter should be close to original size to maintain accurate speedometer and odometer readings. Use a tire size calculator to compare overall diameters.
Vehicle Handling: Going slightly wider can improve handling but make sure it matches your driving needs and vehicle specs.
Conclusion
Changing 235 to 255 tires is a decision that requires careful thought of many factors, fitment, vehicle performance, safety and legal regulations.
Follow the steps in this guide and the related sub-topics and you can make an informed decision that balances aesthetics, performance and practicality.
Always remember to read your vehicle’s manual and seek professional advice to ensure a safe and successful tire upgrade.
Citations
- Tire Rack: “Understanding Tire Sizes and Specifications” (https://www.tirerack.com/content/tirerack/desktop/en/tire_buying_guide.html)
- Car and Driver: “The Effects of Tire Width on Performance” (https://www.caranddriver.com/features/a15130283/how-tires-affect-performance/)
- Consumer Reports: “The Impact of Tire Size on Fuel Economy” (https://www.consumerreports.org/cro/tire-buying-guide.htm)
