The 2018 Audi A5 Quattro sits in the modern sport-luxury coupe and cabriolet segment, blending clean Audi design with all-wheel-drive confidence and a chassis tuned for everyday refinement. Buyers looking at this generation often care just as much about maintaining the car’s composed road manners and crisp appearance as they do outright performance. Tire fitment centers on two radial sizes, 245/40R18 and 255/35R19, depending on the exact trim and wheel package. That creates a clear choice between 18-inch and 19-inch setups, with additional variation in blackwall, redline, and raised white letter presentations among available products. The right selection starts with confirming the sub-model and wheel diameter already on the car.
Which Tire Size Is Right for The 2018 Audi A5 Quattro
The 2018 Audi A5 Quattro uses two primary tire sizes, and the correct one depends on the exact sub-model and wheel package. Both are radial fitments, but they are built around different rim diameters: 18-inch for 245/40R18 and 19-inch for 255/35R19. Before choosing a tire, the first step is confirming which wheels are on the car, since that determines which size belongs on it.
Fit(s): Premium Plus Cabriolet, Premium Plus Coupe, Prestige Cabriolet, and Prestige Coupe
Construction: Radial|Rim: 19 in
255/35R19 is a metric radial size where 255 is the nominal section width in millimeters, 35 is the aspect ratio, R marks radial construction, and 19 identifies the rim diameter in inches. On the 2018 Audi A5 Quattro, this size belongs to 19-inch wheel applications used on certain Premium Plus and Prestige trims. Product choice in this size centers on blackwall radial tires from BFGoodrich across several g-Force series. This is the size to evaluate when the car already has 19-inch wheels and the objective is staying with the proper diameter and profile family for that setup.
Sub-model fitment matters on the 2018 Audi A5 Quattro because some trims use only the 18-inch tire size, while others may use either the 18-inch or 19-inch setup. Identifying the exact coupe or cabriolet trim helps narrow the choice before comparing brands, sidewall styles, or tire series.
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2018 Audi A5 Quattro Premium Cabriolet
The 2018 Audi A5 Quattro Premium Cabriolet uses the 245/40R18 radial tire size. Tire selection here is mainly about choosing the right 18-inch radial option for the car’s existing wheels and deciding whether a blackwall, redline, or raised white letter look suits the intended presentation.
The 2018 Audi A5 Quattro Premium Coupe also uses the 245/40R18 radial tire size. That keeps the fitment straightforward, so the main comparison becomes brand, tire series, and sidewall style within the proper 18-inch size.
The 2018 Audi A5 Quattro Premium Plus Cabriolet may use either 245/40R18 or 255/35R19, depending on the wheel package on the car. Checking the installed wheel diameter first is essential before selecting a tire, since the two sizes are built for different rim diameters.
The 2018 Audi A5 Quattro Premium Plus Coupe may be equipped with either 245/40R18 or 255/35R19 radial tires. The practical decision is confirming whether the coupe has 18-inch or 19-inch wheels before comparing the available radial tire options in the appropriate size.
The 2018 Audi A5 Quattro Prestige Cabriolet can use either the 245/40R18 or 255/35R19 radial size. That makes wheel verification the first step, followed by choosing the tire series and sidewall treatment that best match the car’s current setup and intended use.
The 2018 Audi A5 Quattro Prestige Coupe may use 245/40R18 or 255/35R19 radial tires, depending on the wheels fitted to the car. Once the rim diameter is confirmed, the tire choice becomes a comparison of available 18-inch or 19-inch radial options rather than a broad fitment guess.
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 2018 Audi A5 Quattro Tires for Sale
Available 2018 Audi A5 Quattro tires cover both 245/40R18 and 255/35R19 radial fitments, with choices from BFGoodrich, Nitto, M&H Racemaster, and Pro-Trac. The product grid is most useful for comparing tire series, blackwall versus redline or RWL sidewall styles, and wheel-width compatibility within the correct size.
These FAQs focus on the exact tire sizes used on the 2018 Audi A5 Quattro, how fitment changes by trim and wheel diameter, and how to compare the available radial tire options for appearance, compatibility, and road use.
Tire Size & Fitment
What tire size fits a 2018 Audi A5 Quattro?
The 2018 Audi A5 Quattro uses two primary tire sizes: 245/40R18 and 255/35R19. Both are radial sizes, but they are tied to different wheel diameters, so the correct choice depends on the exact trim and the wheels currently installed on the car.
Premium Coupe and Premium Cabriolet applications use 245/40R18, while Premium Plus and Prestige coupe and cabriolet versions may use either 245/40R18 or 255/35R19. The most important step is checking whether the car has 18-inch or 19-inch wheels before selecting a tire.
What size rim does a 2018 Audi A5 Quattro use?
A 2018 Audi A5 Quattro uses either an 18-inch or 19-inch rim, depending on the tire size fitted to the vehicle. The 245/40R18 size uses an 18-inch rim, and the 255/35R19 size uses a 19-inch rim.
That means rim diameter has to be confirmed before choosing a tire. Looking only at the model year and name is not enough, because some trims can be equipped with either setup. Wheel diameter should match the tire size exactly, and wheel width should also be checked against the tire’s specifications.
Do all 2018 Audi A5 Quattro sub-models use the same tire size?
No, not all 2018 Audi A5 Quattro sub-models use the same tire size. Premium Coupe and Premium Cabriolet use 245/40R18, while Premium Plus and Prestige coupe and cabriolet versions may use either 245/40R18 or 255/35R19.
That variation usually comes down to the wheel package on the individual car. Before ordering replacement tires, verify the exact trim and then confirm the actual wheels fitted to the vehicle. Two cars with the same year and model name may still need different tires if one has 18-inch wheels and the other has 19-inch wheels.
Choosing the Right Tire
What should I consider when choosing a 245/40R18 tire for a 2018 Audi A5 Quattro?
Start with the correct 245/40R18 size and confirm that the car is one of the 18-inch wheel applications. Available tires in this size include several radial choices with differences in tire series, sidewall appearance, rim-width specifications, and intended character, including street-performance and drag-oriented options.
Once the size is confirmed, compare the tire to the way the car is actually used. A buyer focused on a cleaner modern look may prefer blackwall options, while a more distinctive presentation may point toward redline or RWL. Wheel width should be checked carefully before making a final selection.
What sidewall styles are available for 2018 Audi A5 Quattro tires?
The available sidewall styles for 2018 Audi A5 Quattro tires include blackwall, redline, and RWL, depending on the size and tire series. Blackwall is available in both 245/40R18 and 255/35R19, while redline and RWL appear in the 245/40R18 fitment.
Sidewall choice is mainly an appearance decision once the correct size has been established. On a modern Audi, blackwall keeps a more contemporary presentation, while redline or raised white letter tires create a more customized look. The sidewall style should be chosen only after confirming the proper wheel diameter and tire size for the car.
What brands offer tires for the 2018 Audi A5 Quattro?
Tires for the 2018 Audi A5 Quattro are available from BFGoodrich, Nitto, M&H Racemaster, and Pro-Trac. Brand coverage varies by size, with the broader selection appearing in 245/40R18 and a more focused set of BFGoodrich options in 255/35R19.
Brand should be one part of the decision, but not the only one. The better comparison is size first, then wheel compatibility, tire series, sidewall style, and how the car is driven. That approach helps narrow the options without assuming that every tire offered in one size will suit every A5 Quattro configuration.
Restoration & Appearance
How does tire construction affect the appearance of a restored 2018 Audi A5 Quattro?
On a 2018 Audi A5 Quattro, tire construction does not involve a vintage bias-ply-versus-radial decision, because the primary fitments are radial. The visual effect comes more from the tire’s profile, the wheel diameter, and the sidewall treatment chosen within the proper size.
A blackwall tire generally maintains the clean, contemporary look most buyers associate with this generation, while redline or RWL options in 245/40R18 create a more customized appearance. For a restoration-oriented result, keeping the correct tire size and wheel diameter usually matters more than chasing a dramatic sidewall style.
Does correct tire fitment matter for a 2018 Audi A5 Quattro restoration?
Yes, correct tire fitment matters on a 2018 Audi A5 Quattro because wheel diameter and tire profile are part of the car’s overall stance and visual balance. Using 245/40R18 on an 18-inch setup or 255/35R19 on a 19-inch setup helps preserve the intended proportion of the vehicle.
For restoration-minded owners, the first goal is matching the car’s existing wheel package before comparing sidewall appearance or tire series. If originality is especially important, verify the exact trim and wheel configuration on the individual car so the replacement tire does not unintentionally change its presentation.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2018 Audi A5 Quattro?
Yes, modifications can affect tire fitment on a 2018 Audi A5 Quattro. Changes such as aftermarket wheels, different wheel widths, altered offsets, suspension lowering, or body modifications can all influence whether 245/40R18 or 255/35R19 remains the appropriate choice for the car.
An A5 Quattro with non-original wheels should be checked for wheel diameter, width, and clearance at full steering lock and suspension travel. Even when the tire size sounds correct, a changed setup can alter how the tire sits in the wheelwell. That is especially important before moving between 18-inch and 19-inch applications.
What should I inspect before driving a 2018 Audi A5 Quattro on new tires?
Before driving a 2018 Audi A5 Quattro on new tires, inspect wheel diameter, wheel width, tire pressure, and the overall condition of the suspension and alignment-sensitive components. The tire should match the wheel exactly, and the vehicle should be checked for any existing rubbing, uneven wear, or steering issues.
A short road test after installation is worthwhile to confirm there is no contact under turning or compression. It also helps to recheck inflation pressure and look for any unusual wear pattern developing early. On a car with optional wheel packages, this inspection confirms that the replacement tire matches the actual setup on the vehicle.
How often should tires on a 2018 Audi A5 Quattro be inspected?
Tires on a 2018 Audi A5 Quattro should be inspected regularly, especially on a car that sees seasonal or intermittent use. Tread condition, air pressure, uneven wear, cuts, bulges, and sidewall damage are all worth checking as part of normal ownership, not just when a replacement is already due.
Regular inspection matters even more if the car spends long periods parked, since low-use vehicles can develop age-related condition issues before the tread is worn out. Checking the tires before longer drives is a smart habit, and any change in ride quality, vibration, or steering feel deserves a closer look right away.
