Tacoma Tire Size Calculator
Use this calculator to compare your current Toyota Tacoma tire size with a potential new size. Understand how changes in tire width, aspect ratio, and rim diameter affect overall tire diameter, sidewall height, speedometer accuracy, and effective gearing.
Current Tire Size
New Tire Size
Tire Comparison Results
'; output += 'Current Tire (' + currentTireWidth + '/' + currentAspectRatio + 'R' + currentRimDiameter + '):'; output += ' Overall Diameter: ' + currentMetrics.overallDiameter.toFixed(2) + ' inches'; output += ' Sidewall Height: ' + currentMetrics.sidewallHeight.toFixed(2) + ' inches'; output += ' Revolutions Per Mile: ' + currentMetrics.revolutionsPerMile.toFixed(0) + ''; output += 'New Tire (' + newTireWidth + '/' + newAspectRatio + 'R' + newRimDiameter + '):'; output += ' Overall Diameter: ' + newMetrics.overallDiameter.toFixed(2) + ' inches'; output += ' Sidewall Height: ' + newMetrics.sidewallHeight.toFixed(2) + ' inches'; output += ' Revolutions Per Mile: ' + newMetrics.revolutionsPerMile.toFixed(0) + ''; output += 'Differences:'; output += ' Diameter Change: ' + (diameterDifference > 0 ? '+' : ") + diameterDifference.toFixed(2) + ' inches (' + (diameterPercentageChange > 0 ? '+' : ") + diameterPercentageChange.toFixed(2) + '%)'; output += ' Sidewall Height Change: ' + (sidewallDifference > 0 ? '+' : ") + sidewallDifference.toFixed(2) + ' inches'; output += ' Ground Clearance Change: ' + (diameterDifference / 2 > 0 ? '+' : ") + (diameterDifference / 2).toFixed(2) + ' inches'; output += ' Revolutions Per Mile Change: ' + (revsPerMileDifference > 0 ? '+' : ") + revsPerMileDifference.toFixed(0) + ''; output += 'Speedometer Impact:'; output += ' If your speedometer reads ' + speedometerReadsMPH + ' MPH, your actual speed with the new tires will be approximately ' + actualSpeedMPH.toFixed(1) + ' MPH.'; output += ' This is a ' + (speedometerErrorPercentage > 0 ? '+' : ") + speedometerErrorPercentage.toFixed(2) + '% difference.'; if (speedometerErrorPercentage > 3 || speedometerErrorPercentage < -3) { output += 'Warning: A speedometer error of this magnitude may require recalibration to avoid legal issues or inaccurate readings.'; } else if (speedometerErrorPercentage !== 0) { output += 'Consider this speedometer difference when driving.'; } else { output += 'No significant speedometer error detected.'; } resultsDiv.innerHTML = output; }Understanding Your Tacoma's Tire Sizes
Changing tire sizes on your Toyota Tacoma is a popular modification, whether for aesthetics, off-road performance, or simply replacing worn-out tires. However, it's crucial to understand the implications of these changes. This calculator helps you visualize the impact of different tire dimensions.
What do the numbers mean? (e.g., 265/75R16)
- 265 (Tire Width in mm): This is the width of the tire in millimeters, measured from sidewall to sidewall. A wider tire can offer more grip but might also lead to rubbing issues or require wheel spacers.
- 75 (Aspect Ratio %): This number represents the height of the tire's sidewall as a percentage of its width. In this example, the sidewall height is 75% of 265mm. A higher aspect ratio means a taller sidewall, which can improve ride comfort and off-road capability by allowing more flex. A lower aspect ratio means a shorter sidewall, often found on performance tires, offering sharper handling but a harsher ride.
- R (Construction Type): "R" stands for Radial, the most common type of tire construction today.
- 16 (Rim Diameter in inches): This is the diameter of the wheel (rim) that the tire is designed to fit, measured in inches. Changing rim diameter often necessitates a change in aspect ratio to maintain a similar overall tire diameter.
Why do tire size changes matter for your Tacoma?
- Speedometer Accuracy: The most immediate and common effect. Your Tacoma's speedometer is calibrated for its factory tire size. Changing the overall diameter of your tires will cause your speedometer to read inaccurately. A larger tire will make your speedometer read slower than your actual speed, while a smaller tire will make it read faster.
- Ground Clearance: A larger overall tire diameter directly increases your vehicle's ground clearance by half the increase in diameter. This is beneficial for off-roading.
- Effective Gearing: Larger tires effectively "raise" your gear ratio. This means your engine will have to work harder to turn the wheels, potentially reducing acceleration, fuel economy, and increasing strain on the drivetrain, especially if you have a smaller engine or tow frequently.
- Rubbing/Clearance Issues: Taller or wider tires might rub against your Tacoma's fender wells, suspension components, or frame, especially during turns or when the suspension is compressed. This often necessitates modifications like a lift kit, fender trimming, or wheel spacers.
- Braking Performance: Larger, heavier tires can increase rotational mass, potentially affecting braking performance and requiring more effort to stop.
- Fuel Economy: Generally, larger and heavier tires can decrease fuel efficiency due due to increased rolling resistance and the engine working harder.
Always consider these factors and consult with a professional or Tacoma-specific forums (like TacomaWorld!) before making significant tire size changes to ensure safety and optimal performance for your vehicle.