The 2009 Audi S6 belongs to a period when Audi was blending executive-sedan comfort with serious all-wheel-drive performance, giving the S6 a distinctly understated but very capable character. Buyers looking at this exact car are usually balancing everyday road manners with the sharp, planted feel expected from a modern German sport sedan. Tire fitment centers on radial sizes 255/40R18 and 265/35R19, so the first step is confirming which wheel diameter is on the car. Available choices stay within a blackwall performance theme, with multiple series from BFGoodrich and an additional Nitto option in 19-inch fitment. The right selection depends on wheel setup, intended driving use, and whether the car remains stock or has been modified.
Which Tire Size Is Right for The 2009 Audi S6
The 2009 Audi S6 uses two primary tire sizes, and the difference comes down to wheel diameter rather than a change from radial to bias-ply construction. Both sizes are modern radial fitments, but one is built for an 18-inch rim and the other for a 19-inch rim. Before choosing a tire, the most important step is confirming which wheels are actually on the car, especially if it has seen aftermarket wheel changes.
255/40R18 is a modern metric radial size where 255 is the nominal section width in millimeters, 40 is the aspect ratio, R identifies radial construction, and 18 is the wheel diameter in inches. On the 2009 Audi S6, this size supports the car's modern sport-sedan character while keeping the fitment tied to an 18-inch wheel. Available choices in this size come from BFGoodrich across the g-Force Comp 2 AS, g-Force Sport Comp 2, and g-Force Phenom T/A series, all in blackwall form. This size is the right one to evaluate only after confirming that the car is still using 18-inch wheels.
265/35R19 is also a modern metric radial size, with 265 indicating nominal section width in millimeters, 35 indicating the aspect ratio, and 19 identifying the wheel diameter in inches. For the 2009 Audi S6, it represents the 19-inch fitment and keeps the car in a low-profile radial format suited to larger-diameter wheels. Product choices in this size include BFGoodrich and Nitto, with blackwall offerings in the g-Force Sport Comp 2, g-Force Phenom T/A, and NT555 G2 lines. This is the size to pursue when the S6 is equipped with 19-inch wheels and the goal is staying with that wheel-and-tire setup.
Fitment is straightforward because the covered 2009 Audi S6 sub-model shares the same two radial size paths. The important distinction is not trim level, but whether the car is riding on 18-inch or 19-inch wheels before a tire is selected.
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2009 Audi S6 Base
The 2009 Audi S6 Base uses the same two radial fitment choices found at the model level, so tire selection starts with wheel diameter confirmation rather than sub-model differentiation. Once the wheel size is verified, the decision shifts to comparing available blackwall performance tires by brand, series, and rim-width suitability where stated.
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Best 2009 Audi S6 Tires for Sale
Available 2009 Audi S6 tire choices stay within modern radial blackwall performance offerings. The 18-inch fitment centers on BFGoodrich g-Force series options, while the 19-inch fitment adds both BFGoodrich and Nitto choices with some variation in tire series and rim-width specification.
These FAQs focus on the exact tire sizes used on the 2009 Audi S6, how to confirm the correct wheel fitment, and how to compare the available radial performance tire choices for appearance, compatibility, and road use.
Tire Size & Fitment
What tire size fits a 2009 Audi S6?
The 2009 Audi S6 uses two tire sizes: 255/40R18 and 265/35R19. Both are radial fitments, and both apply to the S6 Base, so the difference is tied to wheel diameter rather than to a separate sub-model with a different construction type.
That means the key fitment step is checking whether the car has 18-inch or 19-inch wheels before choosing a tire. Many S6 sedans remain stock, but aftermarket wheels can change the setup, so it is smart to verify the wheel diameter and compare the existing tire size on the car before ordering replacements.
What size rim does a 2009 Audi S6 use?
A 2009 Audi S6 uses either an 18-inch rim with 255/40R18 tires or a 19-inch rim with 265/35R19 tires. Both sizes are modern radial fitments, and the rim diameter is built directly into the tire size code.
The final number in each size is the wheel diameter, so an 18-inch tire cannot be mounted on a 19-inch wheel, and the reverse is also true. Beyond diameter, wheel width can matter as well, especially when comparing among replacement tires that carry their own approved rim-width ranges.
Does the 2009 Audi S6 Base use the same tire size?
The 2009 Audi S6 Base uses the same two model-level tire sizes: 255/40R18 and 265/35R19. Both are radial sizes, so there is no separate Base-only construction or special alternate format to decode.
That keeps the fitment question simple, but it does not remove the need to inspect the car itself. The practical check is confirming which wheels are currently installed, since the Base can be on either size path and prior owners may have changed wheels or tires from the original configuration.
Choosing the Right Tire
What should I consider when choosing a 255/40R18 tire for a 2009 Audi S6?
A 255/40R18 tire for a 2009 Audi S6 should first match the car's 18-inch wheel setup, then be compared by construction, tire series, and wheel compatibility. In this size, the available choices are radial blackwall performance tires from BFGoodrich, including the g-Force Comp 2 AS, g-Force Sport Comp 2, and g-Force Phenom T/A.
Selection comes down to how the car is used and whether the wheel width falls within the tire's approved range. It also helps to compare details such as load figures where stated, overall tire weight, and whether the car is kept in stock form or used in a more aggressive street-driving role.
What brands offer tires for the 2009 Audi S6?
Tires for the 2009 Audi S6 are available from BFGoodrich and Nitto across the two supported sizes. BFGoodrich appears in both 18-inch and 19-inch fitments, while Nitto is represented in the 265/35R19 size.
Brand choice matters less than getting the correct size and wheel match first. After that, compare which brand is offered in the size on your car, then look at the tire series, sidewall treatment, and any stated rim-width or load information to decide which option best suits the S6's current setup.
What tire series are available for the 2009 Audi S6?
The 2009 Audi S6 is covered by several tire series, including BFGoodrich g-Force Comp 2 AS, g-Force Sport Comp 2, g-Force Phenom T/A, and the Nitto NT555 G2 in the 19-inch fitment. All of the available products are radial blackwall tires.
Series names help separate the choices in the product grid, especially when more than one option exists in the same size. Once the correct wheel diameter is confirmed, comparing series is a useful way to narrow the field without drifting away from the S6's required 18-inch or 19-inch fitment.
Restoration & Appearance
Which tire should I choose for a period-style 2009 Audi S6?
A period-style approach for a 2009 Audi S6 starts with keeping the correct size and wheel diameter already used on the car, either 255/40R18 or 265/35R19. Since the available products are all blackwall radial performance tires, the visual presentation stays in line with the clean, contemporary appearance expected from this era of S6.
The practical choice is less about whitewall or vintage sidewall styling and more about preserving the car's modern executive-sport look. Owners focused on originality should also compare the installed wheels, tire proportions, and any surviving delivery or dealer documentation before changing from one wheel-and-tire package to the other.
Does correct tire fitment matter for a 2009 Audi S6 restoration?
Correct tire fitment matters on a 2009 Audi S6 restoration because the car's stance, wheel fill, and overall presentation depend heavily on matching the proper radial size to the wheel diameter. Using 255/40R18 on an 18-inch setup or 265/35R19 on a 19-inch setup keeps the restoration grounded in the proper fitment range for the model.
Appearance is only one part of the issue. The wrong size can also alter how the tire sits in the wheel opening or interacts with the suspension and steering system, so restoration-minded buyers should inspect the current wheels carefully and avoid assuming that any low-profile modern tire will suit the S6 equally well.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2009 Audi S6?
Modifications can affect tire fitment on a 2009 Audi S6, even when the tire size itself appears close to stock. Wheel diameter, wheel width, offset, suspension height, and brake-clearance changes can all influence whether 255/40R18 or 265/35R19 remains the appropriate fitment on an individual car.
A car with aftermarket wheels or altered ride height should be checked more carefully than an unmodified example. Measuring the installed wheel setup and looking at inner clearance, outer fender room, and steering sweep can prevent choosing a tire that matches the size code but does not suit the car's actual configuration.
What should I inspect before driving a 2009 Audi S6 on new tires?
Before driving a 2009 Audi S6 on new tires, inspect the wheels for the correct diameter, visible damage, and proper bead-seat condition, then confirm the new tires match the intended size. It is also wise to check alignment condition, valve stems, and general suspension health so the new radials are not compromised immediately.
Road use depends on more than fresh tread alone. Tire pressure should be set correctly, lug hardware should be properly secured, and the first miles should include a quick recheck for rubbing, vibration, or uneven behavior that could point to wheel, balance, or fitment issues rather than to the tire itself.
How often should tires on a 2009 Audi S6 be inspected?
Tires on a 2009 Audi S6 should be inspected regularly, not just when tread looks low. A quick visual check before longer drives and a more thorough inspection at routine service intervals helps catch air loss, sidewall damage, uneven wear, or impact-related issues that can develop on low-profile performance tires.
Collector storage is less of a concern here than it is on older classics, but age and inactivity still matter. Cars that sit for long periods should have pressures checked more often, and any vibration, flat-spot feel, or visible cracking deserves attention before the S6 is put back into regular road use.
