What is the recommended tire pressure for a 2024 Lexus IS?

The 2024 Lexus IS uses 35 PSI cold on the front axle and 38 PSI cold on the rear axle. These are the OEM specifications. Always measure tire pressure when the tires are cold — before driving or after sitting for at least 3 hours.

What tire size does the 2024 Lexus IS use?

The standard (base trim) tire size for the 2024 Lexus IS is 225/40R18. Higher trim levels and optional packages may use a different size — check the sticker inside your driver's door for the exact specification for your vehicle.

How do I convert the 2024 Lexus IS tire pressure to bar?

35 PSI = 2.4 bar (front) and 38 PSI = 2.6 bar (rear). In kPa: 241 kPa front and 262 kPa rear. Multiply PSI × 0.0689 to convert to bar.

Why are the front and rear tire pressures different on the 2024 Lexus IS?

The 2024 Lexus IS uses 35 PSI front and 38 PSI rear because the two axles carry different loads. The front axle carries roughly 51% of the vehicle's 1595 kg curb weight, requiring a slightly different pressure to maintain the correct contact patch at each corner.

What happens if the 2024 Lexus IS tires are underinflated?

Running 5+ PSI low on the Lexus IS causes uneven shoulder wear, increased rolling resistance (worse fuel economy), higher tire operating temperature, and reduced wet braking performance. In extreme cases, chronic underinflation can cause sidewall failure. Check pressure monthly and always after a large temperature swing.

What do the numbers in 225/40R18 mean on the 2024 Lexus IS?

On the 2024 Lexus IS, 225/40R18 breaks down as: 225 = section width in millimetres (8.86"), 40 = aspect ratio (the sidewall is 40% of the width, so 90 mm / 3.54" tall), R = radial construction, and 18 = the wheel diameter in inches.

What is the overall diameter of the 2024 Lexus IS tires?

The 225/40R18 tire on the 2024 Lexus IS has an overall diameter of about 25.09" (637 mm) and a rolling circumference of roughly 78.81", giving about 804 revolutions per mile. Fitting a tire with a different diameter will throw off your speedometer and odometer.

2024 Lexus IS Tire Pressure

OEM cold pressure spec — verified for the 2021–2024 generation.

Recommended cold pressure

Front

35PSI

241 kPa

Rear

38PSI

262 kPa

Tire size

225/40R18

Curb weight

1,595 kg

Front axle

51%

2024 Lexus IS tire size: 225/40R18

The factory (base-trim) tire size for the 2024 Lexus IS is 225/40R18. Here is what that size measures out to in the real world — useful when comparing replacement tires or checking whether a different size will fit.

Section width

225 mm

8.86"

Aspect ratio

40%

90 mm sidewall

Wheel diameter

18"

rim

Overall diameter: 25.09"; 637 mm
Sidewall height: 3.54"; 90 mm
Circumference: 78.81"; rolling
Revs / mile: 804; approx.

Staying within ±3% of the 25.09" overall diameter keeps your speedometer accurate. A larger diameter reads slower than your true speed; a smaller one reads faster.

Custom adjustment

Tune for your load & driving style

Pre-filled with Lexus IS specs. Adjust weight or style below.

Recommended COLD pressure

34.7 / 33.3 PSI

Front (cold): 34.7 PSI(2.39 bar)
Rear (cold): 33.3 PSI(2.3 bar)
Front (hot est.): 38.1 PSI
Rear (hot est.): 36.6 PSI

Street setting: balanced for comfort, wear, and fuel economy. Always measure cold.

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Other Lexus IS years

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FAQ

2024 Lexus IS

What is the recommended tire pressure for a 2024 Lexus IS?: The 2024 Lexus IS uses 35 PSI cold on the front axle and 38 PSI cold on the rear axle. These are the OEM specifications. Always measure tire pressure when the tires are cold — before driving or after sitting for at least 3 hours.
What tire size does the 2024 Lexus IS use?: The standard (base trim) tire size for the 2024 Lexus IS is 225/40R18. Higher trim levels and optional packages may use a different size — check the sticker inside your driver's door for the exact specification for your vehicle.
How do I convert the 2024 Lexus IS tire pressure to bar?: 35 PSI = 2.4 bar (front) and 38 PSI = 2.6 bar (rear). In kPa: 241 kPa front and 262 kPa rear. Multiply PSI × 0.0689 to convert to bar.
Why are the front and rear tire pressures different on the 2024 Lexus IS?: The 2024 Lexus IS uses 35 PSI front and 38 PSI rear because the two axles carry different loads. The front axle carries roughly 51% of the vehicle's 1595 kg curb weight, requiring a slightly different pressure to maintain the correct contact patch at each corner.
What happens if the 2024 Lexus IS tires are underinflated?: Running 5+ PSI low on the Lexus IS causes uneven shoulder wear, increased rolling resistance (worse fuel economy), higher tire operating temperature, and reduced wet braking performance. In extreme cases, chronic underinflation can cause sidewall failure. Check pressure monthly and always after a large temperature swing.
What do the numbers in 225/40R18 mean on the 2024 Lexus IS?: On the 2024 Lexus IS, 225/40R18 breaks down as: 225 = section width in millimetres (8.86"), 40 = aspect ratio (the sidewall is 40% of the width, so 90 mm / 3.54" tall), R = radial construction, and 18 = the wheel diameter in inches.
What is the overall diameter of the 2024 Lexus IS tires?: The 225/40R18 tire on the 2024 Lexus IS has an overall diameter of about 25.09" (637 mm) and a rolling circumference of roughly 78.81", giving about 804 revolutions per mile. Fitting a tire with a different diameter will throw off your speedometer and odometer.