Audi Fox Tires

Audi Fox models from 1973 through 1979 use two listed tire sizes: 155R13 and 175/70R13. Both sizes are radial constructions and both fit 13-inch wheels. The 155R13 products shown are built for 13-inch rims, with examples covering 4.00 to 5.50 inch wheel widths, while the 175/70R13 product shown is built for a 13-inch rim with a 4.5 to 6.0 inch wheel width range.

That means the main fitment question is not the model year, since both sizes appear across the full run, but which wheel and tire setup your particular Audi Fox actually carries. Check the size on the current tire, measure or verify the wheel width, and compare that with the intended look and stance before making a final selection.

On an Audi Fox, 155R13 is an older Euro-metric radial size. The 155 refers to a section width of 155 millimeters, the R identifies radial construction, and the 13 is the wheel diameter in inches. Unlike a modern metric size with a slash and aspect ratio, this format typically implies a tall-profile radial often associated with period European small cars.

That matters because 155R13 gives the Audi Fox a different visual profile and likely a different sidewall height than 175/70R13, even though both fit 13-inch rims. If your goal is to preserve a narrower, more original-style appearance, this is the size to verify first against the tire already on the car and the wheel width it uses.

A 1975 Audi Fox has 2 tire sizes listed because both 155R13 and 175/70R13 appear for that model year, and they share the same 13-inch rim diameter. Since the wheel diameter does not change, the split is not caused by a larger or smaller wheel. It reflects a same-year fitment difference centered on tire section width and sidewall profile.

For a buyer or restorer, that means year alone is not enough to identify the correct tire. The practical way to sort it out is to inspect the wheel width, note the size currently installed, and compare the car’s stance and intended use. A narrower touring-style setup points toward 155R13, while a wider lower-profile setup points toward 175/70R13.

A 1977 Audi Fox can use either 155R13 or 175/70R13, so the correct choice comes from the actual wheel and tire setup on the car rather than the year alone. Both are 13-inch radial sizes, but they differ in width and sidewall profile. The available 155R13 products are intended for 13-inch rims with wheel widths starting at 4.00 inches, while the listed 175/70R13 product fits a 13-inch rim with a 4.5 to 6.0 inch wheel width range.

Start by reading the existing tire size and checking the wheel width stamped on the rim or measured bead-to-bead. If the car is a preservation-minded example, compare what is on the car with period photos and marque references. That approach helps you avoid choosing a size that technically mounts but changes the car’s proportions or steering feel.

The available Audi Fox tires in this group are all blackwall designs. The Michelin XAS, Dunlop SP Sport Aquajet, and Avon CR6ZZ listings each use a blackwall sidewall style. There are no whitewall or other decorative sidewall treatments shown for these Audi Fox sizes.

That fits the character of a 1970s European compact sedan, where a plain blackwall radial is usually the most natural visual match. If appearance matters as much as fitment, blackwall construction keeps the look restrained and period-appropriate while still letting you choose between a taller narrow tire and a lower-profile alternative.

Three brands appear in the available Audi Fox tire offerings: Michelin, Dunlop, and Avon. Michelin and Dunlop are listed in 155R13, while Avon is listed in 175/70R13. The series represented are Michelin XAS-FF, SP Sport Aquajet, and CR6ZZ.

Brand choice on an Audi Fox is tied closely to size choice, because not every brand appears in both fitments. If you are choosing primarily on authenticity, tread character, or period European feel, compare the brand options within the size your car actually requires first, then narrow the selection by the driving style and appearance you want.

The available Audi Fox tire series are Michelin XAS-FF, Dunlop SP Sport Aquajet, and Avon CR6ZZ. All three are radial tires, but they are offered in two different sizes rather than as direct like-for-like alternatives across the entire range. Michelin XAS-FF and SP Sport Aquajet are listed in 155R13, while Avon CR6ZZ is listed in 175/70R13.

For an Audi Fox owner, that means the first decision is still fitment, not brand alone. Once the correct size is established, the tire series becomes a way to refine the car’s presentation and intended use, whether the goal is a more original-feeling narrow European radial setup or a wider, lower-profile 13-inch radial appearance.

An Audi Fox should be stored in a cool, dry, dark space with the tires kept away from direct sunlight, ozone sources, and standing moisture. Inflate the tires to a proper storage pressure for the vehicle’s resting condition and make sure the car is parked on a clean surface rather than bare earth. Long idle periods are especially hard on collector-car radials because they can develop flat spotting and sidewall stress even when tread wear is minimal.

If the Audi Fox will sit for months at a time, roll it occasionally or support it in a way that reduces constant load on one contact patch. Clean the tires with mild soap and water only, and avoid dressings that leave a glossy chemical residue. A careful storage routine does more to preserve vintage-style tires than low annual mileage alone.

Tires on an Audi Fox should be inspected before regular road use and again after long storage periods, even if the car is driven only occasionally. Look for cracking, bulges, tread separation, impact damage, irregular shoulder wear, and any change in how the tire seats on the rim. Because the Audi Fox uses relatively narrow 13-inch radials, even small condition changes can affect tracking, braking feel, and ride quality.

A practical habit is to inspect the tires at the start of each driving season and any time the car has been parked for several weeks. Check inflation, valve condition, and tread wear across the full width. If the car pulls, vibrates, or suddenly feels less settled than usual, stop treating the tires as a cosmetic item and have the assembly examined closely.

Audi Fox tires should be replaced when age, cracking, sidewall deterioration, impact damage, or long-term storage effects make the casing questionable, even if the tread still looks deep. Collector cars often age out their tires long before they wear them out. A radial that appears presentable can still be unsuitable for service if the rubber has hardened or the internal structure has degraded.

Treat age and condition as equal to tread depth when evaluating tires on an Audi Fox. If the car is new to you, verify the age of every tire before putting miles on it. Replacement is the right call whenever there is doubt about structural integrity, because a vintage sedan driven occasionally can still stress an old tire with heat cycles, cornering loads, and emergency braking.

Audi Fox listings in this group include both 155R13 and 175/70R13, with all available products built as blackwall radial tires. The product range also spans more than one series, including Michelin XAS-FF, Dunlop SP Sport Aquajet, and Avon CR6ZZ. That tells you the Audi Fox sits in a period where more than one radial approach can be appropriate depending on the exact car and wheel setup.

For a restoration, originality should be judged against the specific car rather than the model line as a whole. Compare surviving tires, owner literature, period photographs, and marque-club references before settling on one size. Getting the width and profile right has a visible effect on stance, and on a compact European sedan that visual proportion is part of the car’s authenticity.

Correct tire fitment can affect both presentation and judging on an Audi Fox because the tire size, profile, and sidewall style contribute heavily to the car’s period look. In this case, the difference between 155R13 and 175/70R13 is noticeable even though both fit 13-inch wheels. All of the available products shown are blackwall radials, which suits the Fox’s era and character.

For a casual driver, the difference may be mostly visual and dynamic, but for a restoration-minded owner it can influence how complete and correct the car appears. Judges and marque specialists usually look for proportions that match the intended configuration of the individual car. Choosing a size simply because it mounts can undercut an otherwise careful restoration.

For the Audi Fox, Michelin XAS-FF and Dunlop SP Sport Aquajet are both offered in 155R13 and both are blackwall radial tires for 13-inch rims. The practical difference in this context is not size or construction, since those are shared, but the specific series design and brand character. Each represents a period-style radial option for the narrower Audi Fox fitment.

That makes the choice more about the kind of restoration or driving impression you want than about basic compatibility. Owners chasing a distinctly period European tire presentation often compare series names carefully, especially on 1970s imports where tire identity is part of the visual story. Once the car is confirmed to need 155R13, the series choice becomes a finishing detail rather than a fitment decision.

These Audi Fox tires are modern radial products in the listed sizes, so they are intended for real road use when they are correctly matched to the wheel and vehicle condition. Safety depends on far more than the size stamped on the sidewall, though. Wheel width, tire age, inflation, suspension condition, and brake performance all affect how securely an Audi Fox behaves in traffic.

A sound approach is to treat the tire choice as one part of the car’s overall roadworthiness. Make sure the chosen size matches the rim, inspect the tires before use, and confirm that the chassis is aligned and mechanically healthy. A properly sorted Audi Fox can be an enjoyable road car, but an incorrectly matched or aged tire can undo that very quickly.

Before driving an Audi Fox, check tire inflation, visible sidewall condition, tread condition, valve stems, and whether the tire size on the car matches the intended wheel setup. Since both 155R13 and 175/70R13 appear for the model, verify that all four tires are the same size unless the car has a deliberate and well-understood setup. Also look for uneven wear that might point to alignment or suspension issues.

Beyond the tires, make sure the brakes, steering, and wheel fasteners are in proper condition before using the car at speed. A short, careful test drive after any tire change is worthwhile to confirm there is no rubbing, wandering, or vibration. That simple routine helps catch fitment mistakes before they become road problems.

A sensible road speed for an Audi Fox depends on the exact tire fitted, its condition, and the condition of the car as a whole rather than on the model name alone. The listed Audi Fox products are H-rated radial tires in the sizes shown, but a collector car should never be driven according to speed rating alone. Stability, braking margin, heat buildup, and the age of the tire all matter just as much.

In practice, drive an Audi Fox at speeds that suit the tire’s condition and the mechanical state of the car, not the maximum capability suggested by a modern rating code. Fresh, properly fitted tires on a well-maintained car allow more confidence than old or mismatched ones. Conservative cruising remains the right habit, especially after installing newly selected tires or returning the car to service after storage.