Drivers moving to 235/40R18 tires often look for a more direct road feel while still expecting dependable traction and everyday usability in varied driving conditions. Top 5 Tire Recommendations for 235/40R18 (by conditions) include:
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235/40R18 Tire Size
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All You Need to Know About 235/40R18 Tires
235/40R18 tires have a section width of 235 millimeters (mm), an aspect ratio of 40%, radial construction, and an 18-inch wheel diameter. Before buying tires sized 235/40R18, converting the 235/40R18 size to inches, comparing it with similar tire sizes like 225/40R18, and researching the best 235/40R18 tires help drivers shop for the right set for their vehicles.
What Are The Dimensions of 235/40R18 Tires in Inches?
235/40R18 tires have a section width of 9.25 inches, a tire aspect ratio of 3.70 inches, and a wheel diameter of 18 inches. The overall tire diameter of 235/40R18 is ≈ 25.40 inches, circumference of ≈ 79.81 inches, and recommended rim width range of 8.0 inches to 9.5 inches.
235/40R18 tire size in millimeters and inches is presented in the below table:
235/40R18 Tire Size Dimensions | 235/40R18 Tire Size Dimensions in Inches (") | Formula to Convert 235/40R18 Size in Inches (") |
235 mm (section width) | ≈ 9.25" | 235 ÷ 25.4 = 9.25 |
94 mm (sidewall height) | ≈ 3.70" | (235 × 0.40) ÷ 25.4 = 3.70 |
18 (rim diameter) | 18" | Given |
645 mm (overall diameter) | ≈ 25.40" | (2 × 94 ÷ 25.4) + 18 = 25.40 |
2027 mm (circumference) | ≈ 79.80" | 25.40 × 3.1416 = 79.80 |
323 mm (radius) | ≈ 12.70" | 25.40 ÷ 2 = 12.70 |
In inches, the 235/40R18 tire size can be represented as 25.4" × 9.3" R18.
Most Recommended 235/40R18 Tires
What Is The Difference Between 235/40R18 vs 225/40R18?
The main difference between 235/40R18 and 225/40R18 is the section width. 235/40R18 is 10 mm (≈0.39 inches) wider than 225/40R18, which results in a slightly taller sidewall (+4 mm / 0.16 in) and a larger overall diameter (+8 mm / 0.32 in) in the 235/40R18 compared to the 225/40R18 tire size.
The tire dimensions or measurement difference between 235/40R18 vs 225/40R18 is shown in the below table.
Tire Dimensions | 225/40R18 tires dimensions in millimeters (mm) and inches (") | 235/40R18 tires dimensions in millimeters (mm) and inches (") | Difference b/w 225/40R18 and 235/40R18 in millimeters (mm) and inches (") | Percentage ≈ difference b/w 225/40R18 and 235/40R18 |
Section Width | 225 mm (8.86") | 235 mm (9.25") | 10 mm (0.39") | 4.44 % |
Sidewall Height | 90 mm (3.54") | 94 mm (3.70") | 4 mm (0.16") | 4.44 % |
Overall Diameter | 637 mm (25.08") | 645 mm (25.40") | 8 mm (0.32") | 1.27 % |
Circumference | 2001 mm (78.78") | 2027 mm (79.80") | 26 mm (1.02") | 1.27 % |
Radius | 318.5 mm (12.54") | 322.5 mm (12.70") | 4 mm (0.16") | 1.27 % |
Rim Diameter | 457.2 mm (18.00") | 457.2 mm (18.00") | – | – |
Rim Width Range | 7.5” – 9.0” | 8.0” – 9.5” | – | – |
Can I use 225/40R18 instead of 235/40R18?
Yes, using a 225/40R18 tire size instead of a 235/40R18 is generally accepted, provided your wheels are 8.0"–9.0" wide. You can expect minor speedometer differences of about 1.3% and less ground clearance (about 0.15’’) due to a 0.31-inch (8 mm) smaller diameter of the 225/40R18 compared to the 235/40R18 tire size.
You can possibly experience a marginal improvement in fuel efficiency, but the grip can decrease slightly. Also, the 225/40R18 tire size can look a little stretched if your OE size is 235/40R18; however, this will depend mostly on your wheel width.
All You Need to Know About 235/40R18 Tires
235/40R18 tires have a section width of 235 millimeters (mm), an aspect ratio of 40%, radial construction, and an 18-inch wheel diameter. Before buying tires sized 235/40R18, converting the 235/40R18 size to inches, comparing it with similar tire sizes like 225/40R18, and researching the best 235/40R18 tires help drivers shop for the right set for their vehicles.
What Are The Dimensions of 235/40R18 Tires in Inches?
235/40R18 tires have a section width of 9.25 inches, a tire aspect ratio of 3.70 inches, and a wheel diameter of 18 inches. The overall tire diameter of 235/40R18 is ≈ 25.40 inches, circumference of ≈ 79.81 inches, and recommended rim width range of 8.0 inches to 9.5 inches.
235/40R18 tire size in millimeters and inches is presented in the below table:
235/40R18 Tire Size Dimensions | 235/40R18 Tire Size Dimensions in Inches (") | Formula to Convert 235/40R18 Size in Inches (") |
235 mm (section width) | ≈ 9.25" | 235 ÷ 25.4 = 9.25 |
94 mm (sidewall height) | ≈ 3.70" | (235 × 0.40) ÷ 25.4 = 3.70 |
18 (rim diameter) | 18" | Given |
645 mm (overall diameter) | ≈ 25.40" | (2 × 94 ÷ 25.4) + 18 = 25.40 |
2027 mm (circumference) | ≈ 79.80" | 25.40 × 3.1416 = 79.80 |
323 mm (radius) | ≈ 12.70" | 25.40 ÷ 2 = 12.70 |
In inches, the 235/40R18 tire size can be represented as 25.4" × 9.3" R18.
Most Recommended 235/40R18 Tires
Drivers moving to 235/40R18 tires often look for a more direct road feel while still expecting dependable traction and everyday usability in varied driving conditions. Top 5 Tire Recommendations for 235/40R18 (by conditions) include:
What Is The Difference Between 235/40R18 vs 225/40R18?
The main difference between 235/40R18 and 225/40R18 is the section width. 235/40R18 is 10 mm (≈0.39 inches) wider than 225/40R18, which results in a slightly taller sidewall (+4 mm / 0.16 in) and a larger overall diameter (+8 mm / 0.32 in) in the 235/40R18 compared to the 225/40R18 tire size.
The tire dimensions or measurement difference between 235/40R18 vs 225/40R18 is shown in the below table.
Tire Dimensions | 225/40R18 tires dimensions in millimeters (mm) and inches (") | 235/40R18 tires dimensions in millimeters (mm) and inches (") | Difference b/w 225/40R18 and 235/40R18 in millimeters (mm) and inches (") | Percentage ≈ difference b/w 225/40R18 and 235/40R18 |
Section Width | 225 mm (8.86") | 235 mm (9.25") | 10 mm (0.39") | 4.44 % |
Sidewall Height | 90 mm (3.54") | 94 mm (3.70") | 4 mm (0.16") | 4.44 % |
Overall Diameter | 637 mm (25.08") | 645 mm (25.40") | 8 mm (0.32") | 1.27 % |
Circumference | 2001 mm (78.78") | 2027 mm (79.80") | 26 mm (1.02") | 1.27 % |
Radius | 318.5 mm (12.54") | 322.5 mm (12.70") | 4 mm (0.16") | 1.27 % |
Rim Diameter | 457.2 mm (18.00") | 457.2 mm (18.00") | – | – |
Rim Width Range | 7.5” – 9.0” | 8.0” – 9.5” | – | – |
Can I use 225/40R18 instead of 235/40R18?
Yes, using a 225/40R18 tire size instead of a 235/40R18 is generally accepted, provided your wheels are 8.0"–9.0" wide. You can expect minor speedometer differences of about 1.3% and less ground clearance (about 0.15’’) due to a 0.31-inch (8 mm) smaller diameter of the 225/40R18 compared to the 235/40R18 tire size.
You can possibly experience a marginal improvement in fuel efficiency, but the grip can decrease slightly. Also, the 225/40R18 tire size can look a little stretched if your OE size is 235/40R18; however, this will depend mostly on your wheel width.
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