1974 Saab Sonett Tires

The 1974 Saab Sonett uses two primary tire sizes: 155R15 in radial construction and 560-15 in bias-ply construction. Both are 15-inch fitments, so the main difference is not wheel diameter but the sizing system and tire construction the car is running.

That means the first step is deciding whether the Sonett is staying with a radial setup or a traditional bias-ply setup. Many older cars have been changed over time, so it is smart to confirm the current wheels, compare the tire already on the car, and make sure the selected tire matches the owner’s goals for appearance, driving use, and construction type.

The 1974 Saab Sonett’s applicable tire sizes both use a 15-inch rim diameter. That is true for the 155R15 radial fitment and the 560-15 bias-ply fitment, so either primary size stays within the same basic wheel diameter.

Rim diameter is only part of the fitment picture, especially on a compact specialty car like the Sonett. Wheel width should also be checked before selecting a tire, particularly if the car has replacement wheels or if a radial-equivalent conversion is being considered. Matching the tire to the actual wheel on the car helps avoid clearance and handling surprises.

On a 1974 Saab Sonett, 560-15 is a numeric bias-ply tire size. The 5.60 figure refers to the nominal section width in inches, while 15 is the rim diameter in inches. Unlike a modern metric radial size, it does not use the same millimeter-and-aspect-ratio format most drivers see today.

That matters because a 560-15 should be approached as a vintage bias-ply fitment, not as a modern radial size with a comparable-looking code. Owners choosing this route are usually balancing traditional appearance with correct wheel compatibility, and any move away from it toward a radial equivalent should include a careful check of wheel width and tire clearance.

For the 1974 Saab Sonett, 560-15 is the bias-ply fitment. It uses the older numeric sizing system and is available in traditional bias-ply construction, while 155R15 represents the radial fitment in the same 15-inch wheel diameter.

Choosing between them affects more than just the sidewall lettering. Bias-ply and radial tires present the car differently and may suit different restoration or driving goals, so the decision should be made with the current wheels, intended use, and overall tire proportions in mind rather than treating the two constructions as automatically interchangeable.

The radial equivalents tied to 560-15 are 155R15 and 560R15. The 155R15 is an 80-series metric radial equivalent, while 560R15 is a bias-look radial equivalent that keeps a more traditional visual presentation while using radial construction.

Those sizes give a Saab Sonett owner two different ways to move away from a bias-ply tire, but each one still needs to be checked against the car’s wheel setup. A 4-to-5-inch recommended rim-width range is associated with the equivalents, and wheel width, tire dimensions, and clearance should all be confirmed before making the change.

A 1974 Saab Sonett owner considering a move from 560-15 bias-ply to a radial should start by confirming the actual wheel diameter and width on the car. The relevant radial-equivalent choices are 155R15 and 560R15, and both should be evaluated as alternatives rather than assumed replacements.

Clearance at the fenders, steering, and suspension should be checked next, especially if the Sonett has replacement wheels or any suspension changes. It also helps to inspect the overall condition of the chassis and steering components before the conversion, since a different tire construction can change how the car feels on the road even when the rim diameter stays the same.

Start with the correct primary size and construction for the way the car is being used. The 1974 Saab Sonett gives you a radial path in 155R15 and a bias-ply path in 560-15, so the choice is as much about construction and presentation as it is about pure sizing.

After that, compare the tire’s rim-width specification, brand, series, sidewall style, and load information where available. A restoration-minded Sonett may call for a different look than a car driven regularly, and a modified car should always have its wheel width and clearances checked before settling on a final tire choice.

Sidewall choice depends on which of the Sonett’s two primary sizes you are using. The 155R15 radial options are blackwall, while the 560-15 bias-ply options include blackwall, narrow whitewall, and wide whitewall versions.

That makes sidewall appearance one of the biggest visual decisions on this page, especially for owners leaning toward the bias-ply size. A blackwall radial keeps a restrained European look, while whitewall bias-ply tires create a more stylized vintage presentation. The right pick comes down to the car’s restoration direction, existing wheel treatment, and how authentic or expressive the finished look should be.

The 1974 Saab Sonett has tire options from Firestone, Michelin, Avon, Vredestein, US Royal, Coker Classic, and Pro-Trac. Those brands cover both primary fitment paths, with several radial series in 155R15 and several bias-ply choices in 560-15.

Brand alone should not be the only deciding factor. It helps to compare each tire’s construction, series, sidewall treatment, and rim-width compatibility alongside the car’s intended role. A Sonett kept close to period style may lead in one direction, while a driver-focused car on radial tires may point toward a different type of product within the correct size.

A period-style 1974 Saab Sonett can be approached from two directions. The 560-15 bias-ply size gives the car a more traditional vintage presentation, while 155R15 maintains a distinctly European radial look that also fits the Sonett’s era and character.

The better choice depends on what kind of restoration story the car is telling. Some owners want the visual stance and sidewall presence of a bias-ply tire, while others want a more understated radial presentation in the correct 15-inch format. When exact originality matters, marque-specific references and historical documentation are worth consulting before making a final call.

Tire construction changes the look of a restored 1974 Saab Sonett as much as it changes the driving feel. A 560-15 bias-ply gives the car a more traditional small-car vintage profile, while a 155R15 radial brings a later European-style appearance that still belongs comfortably to the period.

Sidewall style adds another layer to that decision. The radial offerings are blackwall, while the bias-ply size is available in blackwall, narrow whitewall, and wide whitewall form. That means construction and appearance should be chosen together, especially on a compact coupe where tire shape and sidewall treatment are easy to notice from every angle.

Yes, modifications can affect tire fitment on a 1974 Saab Sonett even when the tire size itself is correct. Aftermarket wheels, changes in wheel width, suspension alterations, or body and fender work can all change how a 155R15 or 560-15 tire sits on the car.

That is why a Sonett with any non-stock wheel or chassis changes should be measured rather than judged by size code alone. Steering clearance, suspension travel, and fender room deserve a careful look before installation, and that becomes even more important when moving between bias-ply construction and a radial or bias-look radial alternative.

Before driving a 1974 Saab Sonett on new tires, inspect the wheels for correct diameter and sound condition, then confirm that the tires are properly seated and inflated for service. The car’s steering and suspension should also be checked for looseness or wear that could disguise itself as a tire problem once the car is back on the road.

A short, careful test drive is the best next step after installation. Watch for rubbing during turns, listen for contact under suspension movement, and recheck air pressure after the first drive. On a collector car that may have sat for long periods, it also makes sense to inspect the brakes and wheel bearings before putting full trust in the new tires.

Collector-car tires on a 1974 Saab Sonett should be inspected regularly for air loss, tread wear, sidewall cracking, cuts, and bulges, even if the car sees limited mileage. That applies to both 155R15 radials and 560-15 bias-ply tires, since age and storage conditions matter as much as road use on low-mileage vehicles.

Proper storage helps preserve them between drives. Keeping the Sonett away from prolonged sunlight, excess heat, moisture, and ozone sources can reduce premature aging, and maintaining correct inflation helps the tires hold their shape while parked. Any tire that shows visible deterioration should be evaluated before road use, no matter how much tread remains.