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TireSizeStudio guides

Tire and wheel questions answered with the same arithmetic the calculators use.

33 and 35 inch tires in metric sizes

On a 17 in wheel, a 33 in tire is about a 295/70R17 (33.3 in tall) and a 35 is about a 315/75R17 (35.6 in). The first number, the width in millimetres, does not tell you the height on its own: the height comes from the width, the aspect ratio and the wheel together.

What wheel offset do I need

Start from your stock wheel's width and offset, which are stamped inside the wheel, and keep the new wheel's inner edge no further in and its outer edge no further out than you have room for. Going from an 8 in wheel at +45 mm to a 9 in wheel at +35 mm moves the outer edge 23 mm further out and the inner edge 3 mm further in.

How much bigger tire you can fit

Keep the new tire within about 3 percent of the stock tire's overall diameter. At 3 percent larger, the speedometer reads 65 mph when you are doing 67.0, which is about the limit before gearing, ABS and stability control start to notice. Clearance is the other limit: check that the tire clears at full steering lock and full suspension compression.

Load range vs load index

Load range is a light truck tire’s strength class, a letter that sets its maximum pressure: E is the old 10-ply rating, built for 80 psi. Load index is the weight the tire carries at that pressure. An LT265/75R16 in load range E is usually marked 123/120, which is 3,417 lb per tire on a single axle.

Frequently asked questions

What size is a 33 inch tire in metric?
On a 17 in wheel, a 33 in tire is about a 295/70R17 (33.3 in tall) and a 35 is about a 315/75R17 (35.6 in). The first number, the width in millimetres, does not tell you the height on its own: the height comes from the width, the aspect ratio and the wheel together.
What wheel offset do I need?
Start from your stock wheel's width and offset, which are stamped inside the wheel, and keep the new wheel's inner edge no further in and its outer edge no further out than you have room for. Going from an 8 in wheel at +45 mm to a 9 in wheel at +35 mm moves the outer edge 23 mm further out and the inner edge 3 mm further in.
How much bigger tire can I put on my car?
Keep the new tire within about 3 percent of the stock tire's overall diameter. At 3 percent larger, the speedometer reads 65 mph when you are doing 67.0, which is about the limit before gearing, ABS and stability control start to notice. Clearance is the other limit: check that the tire clears at full steering lock and full suspension compression.
What is the difference between load range and load index?
Load range is a light truck tire’s strength class, a letter that sets its maximum pressure: E is the old 10-ply rating, built for 80 psi. Load index is the weight the tire carries at that pressure. An LT265/75R16 in load range E is usually marked 123/120, which is 3,417 lb per tire on a single axle.

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