1972 Subaru GL Tires

The 1972 Subaru GL uses two primary tire sizes: 145R13 in radial construction and 6.15-13 in bias-ply construction. Both sizes are built around a 13-inch wheel, so the main distinction is not wheel diameter but the tire sizing system and construction type used on the car.

Choosing between them starts with confirming how the car is currently set up and what type of driving or restoration goal matters most. A Subaru that has remained close to period specification may stay with 6.15-13 bias-ply tires, while a car already using radial-compatible wheels and road-use expectations may be better evaluated around the 145R13 size.

The 1972 Subaru GL uses a 13-inch rim with both of its primary tire sizes. That applies to the 145R13 radial fitment and the 6.15-13 bias-ply fitment, so wheel diameter remains consistent even though the two tire formats are different.

Wheel diameter is only part of the fitment picture on a small vintage car. It is still important to confirm the actual wheel width on the car, especially if the Subaru has been modified or has replacement wheels. That becomes more important when selecting among available 145R13 radial products, since one Firestone option includes a stated rim-width range of 4.00 to 5.00 inches.

6.15-13 is a vintage numeric bias-ply tire size. The 6.15 refers to the tire’s nominal section width in inches, while 13 refers to the wheel diameter in inches. On the 1972 Subaru GL, it represents the traditional bias-ply fitment path rather than the metric radial format used by 145R13.

That matters because a numeric bias-ply size carries a different construction style and visual character than a radial. Owners trying to preserve a more period-style look often start there, while owners comparing road-use alternatives may also consider whether the car is already set up for radial tires. Wheel condition, clearance, and the actual wheel dimensions should still be checked before any change in construction.

6.15-13 is the bias-ply tire size used on the 1972 Subaru GL. It follows the older numeric sizing format, where the section width is expressed in inches and the final number identifies the 13-inch wheel diameter rather than a modern metric radial construction.

That makes it the more traditional fitment choice for owners who want the car to retain a vintage construction style and appearance. A Subaru already running radial tires or replacement wheels may call for a different evaluation, since changing from bias-ply to radial involves more than matching wheel diameter. Wheel width, tire dimensions, and available clearance should all be confirmed before switching construction types.

Either can be appropriate on a 1972 Subaru GL because both 6.15-13 bias-ply and 145R13 radial fitments are used on this model. The better choice depends on what matters more for the car: maintaining a traditional period-style presentation or using the radial format already associated with 145R13 on the same 13-inch wheel diameter.

A restoration-oriented owner may prefer the visual and historical character of the bias-ply size, while a driver-focused owner may lean toward the radial path. The decision should also take the car’s actual wheel setup into account. A Subaru that has seen wheel replacements, suspension changes, or long-term storage deserves a careful check before settling on either construction.

Start by confirming that the car is using the correct 13-inch wheels and that the wheel width is appropriate for the radial tire being considered. On a 1972 Subaru GL, the radial fitment path is 145R13, and one available Firestone radial in that size carries a stated rim-width range of 4.00 to 5.00 inches.

The next step is checking practical fitment on the vehicle itself. Steering clearance, fender space, suspension condition, and overall tire age all matter on a vintage compact car. It also helps to inspect the wheels for condition and verify that the Subaru has not been altered in ways that affect stance or clearance before making the move from bias-ply to radial construction.

The first consideration is staying with the correct 145R13 size and confirming that the wheel is still a 13-inch rim suited to that radial format. On the 1972 Subaru GL, available 145R13 choices are radial blackwall tires from Michelin and Firestone, so the comparison centers on product characteristics within the same basic fitment.

It helps to look at series, rim-width compatibility where stated, and other details such as weight or load information rather than treating every 145R13 as identical. The car’s intended use also matters. A Subaru being preserved for a period-style presentation may be judged differently than one expected to see regular road miles, even when both remain within the proper size.

The available 145R13 radial products for the 1972 Subaru GL use a blackwall sidewall style. That keeps the visual presentation simple and in scale with a small early-1970s Subaru, without introducing wide whitewall, redline, or raised white letter styling into this particular radial product selection.

Sidewall appearance still matters because it affects how original, understated, or road-ready the car looks once the wheels are mounted. Since the available radial options are blackwall, the main visual decision shifts toward construction choice, overall tire shape, and tire series rather than decorative sidewall treatment. Owners seeking a more traditional look may also compare that presentation against the car’s bias-ply fitment path.

Michelin and Firestone offer applicable 145R13 tires for the 1972 Subaru GL. The Michelin option appears in the XAS-FF series, while Firestone offers the F560 Radial series. Both are blackwall radial choices within the correct 13-inch size family used on this Subaru.

Brand selection should be considered alongside the rest of the fitment details instead of as a shortcut decision. Looking at the specific series, wheel-width compatibility where available, and the overall goal for the car usually leads to a better match. That is especially true on an early Subaru, where preserving the right scale and construction style can matter as much as the brand name on the sidewall.

A period-style 1972 Subaru GL often starts with the 6.15-13 bias-ply size because it reflects the traditional numeric sizing and construction associated with cars of this era. The 145R13 radial is also part of the GL’s fitment picture, but it presents a different construction style and a more modern small-car radial format.

The right choice depends on whether the restoration priority is visual authenticity, driving use, or a compromise between the two. Tire size and construction both influence the car’s stance and character, so they should be chosen carefully. When exact originality matters, period photos, marque-club guidance, and vehicle-specific historical references are worth consulting before settling on a final tire style.

Tire construction changes more than ride characteristics on a restored 1972 Subaru GL. A 6.15-13 bias-ply gives the car a distinctly vintage presentation tied to older numeric sizing, while a 145R13 radial keeps the same 13-inch wheel diameter but introduces a more modern-looking metric radial format.

That visual difference can shape how the car sits and how authentic the finished restoration feels, even before the Subaru is driven. Since the available 145R13 products are blackwall tires, the appearance decision leans heavily on construction and profile rather than decorative sidewall treatments. Owners restoring for show and owners restoring for regular use may reasonably land on different tire choices.

Yes, modifications can affect tire fitment on a 1972 Subaru GL even when the correct basic size is known. Changes to wheels, suspension height, springs, or body clearance can alter how either a 145R13 radial or a 6.15-13 bias-ply sits on the car and how much room remains during steering and suspension movement.

That is why an owner should check the actual setup on the vehicle before choosing tires by size alone. A Subaru with aftermarket wheels may still use a 13-inch diameter but have a different width than expected. Looking at wheel dimensions, visible clearance, and the car’s current ride height helps avoid selecting a tire that only appears correct on paper.

Start with the basics: confirm the wheels are in sound condition, verify that the tire size matches the intended setup, and make sure the tires are properly inflated for service. On a 1972 Subaru GL, it also makes sense to inspect the suspension, steering components, and brake system because a light vintage car is especially sensitive to worn or neglected chassis parts.

A close visual check around the fenders and steering arc is also worthwhile before the first real drive. Even with the correct 13-inch fitment path, old alignment issues, bent wheels, or long-stored components can create problems once the car is back on the road. A short local test drive is a smart final step before relying on the Subaru for longer use.

Collector-car tires on a 1972 Subaru GL should be checked regularly for pressure loss, sidewall cracking, tread separation, cuts, and flat spotting from long periods of storage. Because these cars are often driven less than modern daily vehicles, condition and age can become more important than tread depth alone.

Storage habits matter just as much as inspection. Keeping the Subaru away from prolonged sunlight, moisture, and ozone sources helps preserve the tires, and moving the car occasionally can reduce stress in one contact patch area. Before each driving season or longer trip, it is wise to inspect both the tires and the 13-inch wheels closely rather than assuming low mileage means everything remains road-ready.