Willys 663SS Tires

The Willys 663SS uses 670-15 in the covered year range, which here is 1948. The listed tires for Willys 663SS are bias-ply products built for 15-inch rims, with most fitments centered on rim widths around 4.50 to 5.00 inches and some product-specific variation around that range.

That means the first thing to check on a Willys 663SS is not just the sidewall size, but also whether the car still has the correct 15-inch wheels and suitable rim width. A car that has been restored, modified, or fitted with later replacement wheels can still wear the wrong size even if it looks period correct at a glance.

On a Willys 663SS, 670-15 is a traditional numeric bias-ply size. The 670 refers to a nominal section width of about 6.70 inches, and the 15 identifies the wheel diameter in inches. It is not a modern metric radial code, so it does not express aspect ratio the way a later size such as 205/75R15 would.

That older size format matters because a Willys 663SS should be matched to a tire built for the same style of wheel and driving character. If the car is being restored to stock appearance and feel, staying with the correct numeric bias-ply format preserves the stance, sidewall profile, and steering response expected from a late-1940s Willys.

The listed Willys 663SS tires are all bias-ply products in a period numeric size, and a tube is required. That is the normal arrangement for this type of mid-century collector fitment, especially when using original-style wheels and period-correct tire construction.

When fitting tires to a Willys 663SS, treat the tube as part of the tire system rather than an afterthought. The condition of the wheel, the valve hole, the flap or band arrangement where applicable, and the quality of the tube installation all affect reliability, ride quality, and the long-term health of a low-use collector tire.

For a 1948 Willys 663SS, the listed tire size is 670-15 on a 15-inch rim. The available products show that this size was offered with slightly different recommended rim width ranges depending on brand and series, so the wheel itself deserves a closer look along with the sidewall size.

A good confirmation process for a Willys 663SS starts with the wheel diameter stamp or direct wheel measurement, then moves to any surviving period paperwork, restoration records, or marque-club guidance for that specific car. That approach helps separate an original-style fitment from a later replacement wheel or a cosmetic tire choice made during an older restoration.

Willys 663SS tires are available in blackwall, narrow whitewall, and wide whitewall styles within the 670-15 size. The product range includes plain black sidewalls for a more utilitarian or commercial look, along with several whitewall widths for owners who want a stronger late-1940s passenger-car visual statement.

Choosing among those sidewall styles depends on how a Willys 663SS is being presented. A restrained restoration often favors blackwall or a narrow whitewall, while a more dressy period look may call for a wider band. The best choice is the one that matches the car’s trim level, restoration goal, and the way the car would have appeared in period photos or original literature.

The Willys 663SS tire offerings in 670-15 include Firestone, US Royal, Coker Classic, Universal Vintage Tire, BFGoodrich, Goodyear, Avon, Excelsior, and STA. Those brands appear across several classic bias-ply series, giving Willys 663SS owners a broad mix of appearance options within the same basic size.

For a Willys 663SS, brand choice usually comes down to restoration style, sidewall preference, and how closely an owner wants to echo a particular period look. Once the size and wheel are confirmed, compare the available series and sidewall treatments rather than assuming every 670-15 tire will present the same stance, tread character, or visual presence on the car.

Willys 663SS tires in 670-15 are offered in several series, including Firestone Classic Bias Ply, US Royal Classic Bias Ply, Coker Classic Bias Ply, Universal Classic Bias Ply, Silvertown Classic Bias Ply, Excelsior Bias Ply, Super Cushion, Custom Super Cushion, Super Cushion Deluxe, Turbospeed Mk4, and Super Transport. Most are period-style passenger-car bias-ply lines, while Super Transport is a truck-oriented family and Turbospeed Mk4 is a distinct Avon series within the same basic size range.

That spread gives a Willys 663SS owner room to choose a tire that fits the car’s intended role. A restoration seeking a traditional passenger-car look will usually stay within the classic bias-ply families, while the truck-oriented option deserves extra scrutiny to make sure the visual profile and operating character suit the specific Willys rather than just the nominal size.

A Willys 663SS should be stored in a cool, dry, dark place with the tires kept away from direct sunlight, ozone sources, and prolonged contact with petroleum products or solvents. If the car sits for long periods, maintain proper inflation and move it occasionally so the same section of each bias-ply tire does not carry the load month after month.

Bias-ply tires on a Willys 663SS can flat-spot more readily during storage than modern radials, especially on a collector car that is seldom driven. Using clean floors, tire cradles, or periodic repositioning helps preserve casing shape and ride quality, and it reduces the chance that the car’s first drive after storage feels harsher or less stable than it should.

Tires on a Willys 663SS should be inspected before every meaningful drive and again during routine seasonal servicing, even if the car covers very few miles. Look for cracking, irregular wear, sidewall damage, embedded debris, tread separation signs, and any evidence that the tube, wheel, or bead area may have been compromised.

Collector cars often age their tires out long before they wear them out, and a Willys 663SS is no exception. Frequent inspection matters because problems can develop quietly while the car is parked. A careful look before use is especially important on a bias-ply car, where handling feel, steering effort, and ride quality can change noticeably when a tire begins to deteriorate.

A Willys 663SS tire should be replaced when age, cracking, casing distortion, repeated air loss, or any sign of structural deterioration appears, even if the tread still looks deep. On a low-mile collector car, time and storage history usually matter more than tread depth because the rubber and internal materials continue to age whether the car is driven or not.

That is why a Willys 663SS deserves periodic age review rather than a tread-only approach. If the car has older bias-ply tires from a past restoration, have them evaluated with the same seriousness you would give the brakes or steering. A handsome sidewall and strong tread bars do not guarantee that an older collector tire is still trustworthy for road use.

The covered Willys 663SS fitment is 670-15, and the available offerings are period-style bias-ply tires on 15-inch rims. Several classic passenger-car series are available in that size, which reflects the kind of tire construction and presentation associated with late-1940s American cars without tying the car to a single unsupported original-equipment brand claim.

For a factory-minded Willys 663SS restoration, the exact original tire appearance should be checked against period sales literature, surviving unrestored examples, and marque-club references. That is particularly important when choosing between blackwall, narrow whitewall, and wide whitewall treatments, since all can look plausible unless the restoration is anchored to a specific configuration and era-correct presentation.

Correct tire fitment can absolutely affect both judging and perceived value on a Willys 663SS. Judges and knowledgeable buyers look at size, sidewall treatment, overall stance, and whether the tire construction suits the era. A visibly incorrect profile or an overly modern appearance can change the character of the car even before anyone looks at finer restoration details.

On a Willys 663SS, the right 670-15 bias-ply fitment helps the car sit and present as a proper late-1940s machine. That does not mean every restoration must use the same sidewall style, but it does mean choices should be intentional. Marque clubs and period photos are especially useful when the goal is high-level authenticity rather than simply getting the car rolling.

Willys 663SS tires are available in blackwall, narrow whitewall, and wide whitewall forms, all within the correct 670-15 size. For a late-1940s American restoration, each can be historically plausible depending on how the specific car was equipped and presented, but blackwall generally reads more utilitarian while whitewalls move the appearance toward a more upscale period look.

The right answer for a Willys 663SS restoration depends on the exact personality of the car being recreated. A plain blackwall can suit a businesslike postwar Willys, while a narrow or wider whitewall may better complement bright trim and a more polished show presentation. The strongest choice is the one supported by period imagery or original ownership history for that specific automobile.

A properly fitted, properly maintained bias-ply tire can be suitable for driving a Willys 663SS on public roads within the normal expectations of a late-1940s collector car. The available tires are built in the correct period style, but they should be treated as vintage-type equipment with handling, braking, and ride behavior that differ from a modern radial-equipped car.

That means a Willys 663SS should be driven with generous following distance, moderate cornering loads, and realistic speed expectations for its era and condition. Roadworthiness depends on the full mechanical state of the car as much as the tires themselves, so steering, brakes, wheel bearings, alignment, and wheel condition should all be sorted before any regular road use.

Before driving a Willys 663SS, check tire inflation, visible sidewall condition, tread condition, valve stems, wheel fasteners, and any sign of shifting, rubbing, or bead-seat trouble. Because the listed fitment is a tube-type bias-ply application, it also makes sense to watch for slow leaks or overnight pressure loss that could point to a tube or wheel issue.

A short pre-drive walkaround goes a long way with a Willys 663SS. If the car has been parked for weeks or months, include a careful look for flat spotting and age cracking, then begin the drive gently until the tires warm and settle. Collector cars often spend more time sitting than running, and that changes the tire-check routine compared with a modern daily driver.

A Willys 663SS on period-style bias-ply tires should be driven at moderate, sensible speeds that suit both the tire construction and the overall capabilities of a 1948 automobile. Even when the size is correct, bias-ply tires do not deliver the same straight-line stability, emergency maneuver response, or heat tolerance that drivers expect from modern radial passenger-car tires.

The practical takeaway for a Willys 663SS is to keep speed in line with road conditions, weather, traffic, and the car’s mechanical condition rather than treating modern highway pace as the baseline. A relaxed touring approach is kinder to the tires, more faithful to the character of the car, and generally safer for a collector vehicle built in the immediate postwar era.