1955 Plymouth Tire Fitment Guide

1955 Plymouth vehicles covered here use one tire size: 670-15. That size applies to both the Plymouth P26-1, 26-2 & 26-3 group and the Plymouth P27-1, 27-2 & 27-3 group, and it mounts on a 15-inch rim. Available products for 670-15 list rim-width ranges of 4.50 to 5.00 inches on some applications and 5.00 to 6.00 inches on others, so the specific tire chosen should be matched to the actual wheel.

That shared fitment makes year and make a good starting point, but wheel verification still matters before a final selection. If your car is being restored with original-style steel wheels, check the wheel itself and compare it with the intended tire’s approved rim-width range rather than assuming every 670-15 product is interchangeable across every wheel.

On a 1955 Plymouth tire, 670-15 is a period numeric bias-ply size. The 670 refers to the tire’s nominal section-width class in the older numeric system, while the 15 identifies the rim diameter in inches. Unlike modern metric radial sizing, it does not spell out an aspect ratio in the size code, and the construction here is bias-ply rather than radial.

That matters because a numeric bias-ply tire carries the look and road feel expected on a mid-1950s American car. If you are preserving factory-era appearance, the code itself already points you toward the correct type of tire family, and the remaining choice usually comes down to sidewall style, brand preference, and making sure the wheel width suits the specific product.

Yes, the 1955 Plymouth model groups listed here use the same tire size: 670-15. Both the P26-series group and the P27-series group take that size on 15-inch rims, so there is no split here where one model family needs a different diameter or a different period sizing system.

That simplifies shopping at the year-and-make level, but it does not mean every tire will create the same finished look. A blackwall 670-15 gives a different visual result than a wide whitewall 670-15, and that appearance choice can matter a great deal on a 1955 Plymouth even when the underlying size remains the same.

1955 Plymouth tires in 670-15 are available in both blackwall and wide whitewall form. Blackwall choices appear from Firestone and Universal Vintage Tire, while wide whitewall versions are offered by US Royal and Coker Classic. All are bias-ply tires, so the sidewall decision is mainly about appearance rather than choosing between two different construction types.

A blackwall can suit a simpler driver presentation or a car restored with a more understated look, while a wide whitewall often feels more at home on a mid-1950s American car dressed for show. If authenticity is important, compare the whitewall width and overall visual character with period photos, marque references, and the way your specific Plymouth is being presented.

Four brands offer 670-15 tires for 1955 Plymouth vehicles: Firestone, US Royal, Coker Classic, and Universal Vintage Tire. All of the listed choices are bias-ply products, but they differ in sidewall presentation, with blackwall and wide whitewall options both represented within the size.

Brand choice on a car like a 1955 Plymouth is often tied to the final look as much as the name on the sidewall. Some owners want a familiar domestic brand presence, while others are focused on matching the car’s stance and visual period feel, so it helps to compare the sidewall treatment and wheel-width fit of each brand before settling on one.

The Firestone 670-15 shown for 1955 Plymouth is a blackwall bias-ply tire rated at 1450 pounds at 32 psi, with a listed rim-width range of 4.50 to 5.00 inches and a weight of 23 pounds. The Coker Classic 670-15 is a wide whitewall bias-ply tire rated at 1550 pounds at 32 psi, with a listed rim-width range of 5.00 to 6.00 inches and a weight of 21 pounds.

Those differences matter in two ways: appearance and wheel match. The Firestone suits a blackwall presentation and narrower listed wheel range, while the Coker Classic brings the wide-whitewall look and a wider listed rim range, so the smart approach is to choose the visual style you want first and then confirm that the wheel falls within the intended tire’s approved range.

1955 Plymouth tires in 670-15 are built for 15-inch rims, but the approved rim width depends on the product you choose. Some 670-15 tires list a 4.50 to 5.00 inch rim-width range, while others list 5.00 to 6.00 inches. Even within the same nominal size, the wheel-fit window is not identical from one tire to the next.

That makes wheel measurement worth doing before you commit to a specific brand or sidewall style. If your Plymouth still wears original-style wheels, compare the actual wheel width against the tire you want rather than assuming every 670-15 bias-ply tire is cleared for the same rim range.

The 670-15 tires listed for 1955 Plymouth do not carry TT or TL markings in the size field here, so tube use should be confirmed against the exact tire’s sidewall marking and the wheel being used. On mid-1950s steel wheels, tube fitment can depend on the tire design and the condition and style of the wheel itself as much as the nominal tire size.

That is especially important on a restoration where original wheels may have age, pitting, or design details that affect air retention. Before mounting, inspect the wheel carefully and match the tire to the wheel’s intended use so the final setup is correct for both authenticity and reliable service.

A 1955 Plymouth should be stored away from direct sunlight, standing moisture, and ozone-producing equipment such as electric motors, battery chargers, and welders. Keep the tires properly inflated, park on a clean surface, and move the car periodically if possible. Bias-ply tires are more prone to flat-spotting during long static storage, so extended periods in one position are harder on them than regular exercise.

If the car will sit for a season or longer, many collectors either roll it occasionally or support it in a way that reduces constant load on one section of the tire. Good storage habits help preserve both appearance and ride quality, which matters just as much on a lightly used vintage Plymouth as raw tread depth.

Tires on a 1955 Plymouth should be judged more by age and condition than by mileage. Collector cars often cover few miles, yet the rubber still ages from time, temperature cycles, and storage environment. A sound rule is to begin close inspection in the five-to-seven-year range and treat around ten years as a serious replacement point regardless of tread, using the date code and overall condition together.

That approach is especially sensible on a classic car that may spend long stretches parked and then go out on occasional drives or shows. Sidewall cracking, hardening, poor pressure retention, and vibration after storage can all matter more than visible wear, so age-based maintenance is the safest way to plan ahead.

Tires on a 1955 Plymouth should be inspected before every drive and given a more thorough check before any longer outing. Look for sidewall cracking, cuts, bulges, uneven tread wear, and signs that the tire is losing pressure between uses. The valve stems and the spare should be checked as well, since a seldom-used collector car often reveals age issues there first.

A quick walk-around before local use may be enough for routine driving, but a road trip or show drive deserves extra attention. Catching a small crack, a low tire, or a deteriorated spare in the garage is far easier than dealing with it on the shoulder in a full-size 1955 Plymouth.

A 1955 Plymouth P26-series car would have been fitted in the bias-ply era, and the listed replacement size for the model group is 670-15. That aligns with what buyers expect on a mid-1950s domestic car, where bias-ply construction was standard practice rather than an enthusiast retrofit. Original-equipment brand selection could vary by assembly, market, and supply, so the most important starting points are the correct size, the correct construction type, and the right sidewall look.

If your goal is a factory-style restoration, begin with 670-15 bias-ply and then narrow the appearance details from there. Period photos, original literature, marque clubs, and unrestored examples are the best places to verify whether your particular Plymouth should wear a blackwall or a whitewall presentation for the way it was delivered.

Correct tire fitment matters on a 1955 Plymouth because judges and knowledgeable enthusiasts often notice size, construction type, and sidewall presentation immediately. A 670-15 bias-ply tire suits the car’s period, while a visibly incorrect size or an out-of-era sidewall treatment can distract from an otherwise accurate restoration. On many show fields, the tire is part of the vehicle’s overall visual authenticity, not just a wear item.

The level of scrutiny depends on the event. A local cruise-in may be relaxed, while marque judging or concours-style evaluation can place more emphasis on whitewall width, brand character, and whether the tire looks right for a 1955 Plymouth. If the car is being prepared for serious judging, use club standards and event rules as the final authority.

US Royal and Firestone both offer 670-15 bias-ply tires for the 1955 Plymouth, but they present the car differently. The US Royal version listed here is a 2 11/16-inch wide whitewall rated at 1450 pounds at 32 psi with a 4.50 to 5.00 inch rim-width range and a 22-pound weight, while the Firestone version is a blackwall rated at 1450 pounds at 32 psi with the same 4.50 to 5.00 inch rim-width range and a 23-pound weight.

For restoration purposes, the deciding factor is usually visual authenticity rather than fitment. If your Plymouth is being finished in a dressier mid-fifties style, the US Royal wide whitewall may better suit that presentation, while the Firestone blackwall keeps a cleaner, plainer look. Since their listed wheel range is the same, the appearance difference becomes the main distinction.

A properly maintained 670-15 bias-ply tire in good condition can be used for normal road driving on a 1955 Plymouth, but highway use should always be approached with the car’s age in mind. No speed rating is shown here for the listed products, so the tire should be treated as one part of a much larger system that includes 1950s brakes, steering, suspension, and the condition of the wheels themselves.

That means safety on the highway comes down to preparation rather than assuming a modern-car margin of error. Fresh inspection, correct inflation, a sound front end, and realistic cruising speeds matter more than chasing top-end capability in a full-size mid-1950s Plymouth designed in a very different era of road manners.

The listed 670-15 products for 1955 Plymouth include load-and-pressure figures of 1450 pounds at 32 psi on some tires and 1550 pounds at 32 psi on another. Those figures describe the tire’s rated load at that pressure, not automatically the pressure your Plymouth should run in service. Factory recommendations should come from the owner’s manual or period tire placard for the vehicle, with the tire maker’s published limits respected at the same time.

Use the vehicle recommendation as the operating baseline and the tire’s marked rating as the product limit, not the other way around. Pressure should also be checked cold, because a collector car that sits between uses may lose air gradually without making it obvious until the next drive.

Before a longer drive in a 1955 Plymouth, inspect each tire for cracking, cuts, bulges, uneven wear, and proper cold inflation. Check the valve stems, confirm the spare is usable, and make sure the wheel hardware and wheels themselves are in sound condition. On a bias-ply-equipped car, it is also wise to pay attention to any vibration or flat-spot feel as the car rolls out after storage.

Tire inspection should be part of a broader pre-trip check that includes brakes, steering, suspension, cooling, and lighting. A vintage Plymouth can be very enjoyable on a road trip when everything is sorted, but long-distance confidence comes from checking the whole car carefully rather than focusing on tread alone.