2018 Audi S8 Tire Size

Your 2018 Audi S8 was manufactured with multiple tire sizes.  Choose a tire size below to get a color-coded explanation of the differences.  Then pick the best tire size for your 2018 Audi S8.

Trim Options:

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275/35R21/XL 103Y

Simplified Size:  275-35-21

Simplified size is useful for shopping and buying tires.

The original tire size for your 2018 Audi S8 is 275/35R21/XL 103Y.  A color-coded explanation of the 2018 Audi S8's tire size is shown below.

275

This number indicates that your tire has a width of 275 millimeters.

35

This number means that your tire has an aspect ratio of 35%.  In other words, your tire's sidewall height (from the edge of the rim to the tire's tread) is 35% of the width.  In this case, the sidewall height works out to be 96 millimeters.

R

This letter denotes how your tire was constructed.  Radial is the standard construction method for about 99% of all tires sold today.

RRadial
BBias Belt
DDiagonal
21

The tire size was designed to fit rims or wheels that are 21 inches in diameter.

XL

The mark of XL means extra load.  A tire with this designation can handle higher inflation pressures than a regular tire, which increases its maximum load.

103

This tire has a load index of 103, which means it's capable of carrying a load of 1925 pounds (875 kg) or less.  A higher number means the tire can carry more weight.  A lower number means the opposite.

Y

This tire has a speed rating of Y, which means 186 mph (300 km/h) is the maximum speed that can be sustained for 10 minutes.  A higher speed becomes dangerous.

Trim Options:

Plus

275/35ZR21/XL (103Y)

Simplified Size:  275-35-21

Simplified size is useful for shopping and buying tires.

The original tire size for your 2018 Audi S8 is 275/35ZR21/XL (103Y).  A color-coded explanation of the 2018 Audi S8's tire size is shown below.

275

This number indicates that your tire has a width of 275 millimeters.

35

This number means that your tire has an aspect ratio of 35%.  In other words, your tire's sidewall height (from the edge of the rim to the tire's tread) is 35% of the width.  In this case, the sidewall height works out to be 96 millimeters.

Z

This tire has a speed class of Z, which means it's part of an elite speed class of 149 mph or more (240 km/h).  A tire's speed class is less specific than the speed rating.

R

This letter denotes how your tire was constructed.  Radial is the standard construction method for about 99% of all tires sold today.

RRadial
BBias Belt
DDiagonal
21

The tire size was designed to fit rims or wheels that are 21 inches in diameter.

XL

The mark of XL means extra load.  A tire with this designation can handle higher inflation pressures than a regular tire, which increases its maximum load.

103

This tire has a load index of 103, which means it's capable of carrying a load of 1925 pounds (875 kg) or less.  A higher number means the tire can carry more weight.  A lower number means the opposite.

Y

This tire has a speed rating of Y, which means 186 mph (300 km/h) is the maximum speed that can be sustained for 10 minutes.  A higher speed becomes dangerous.