1955 Buick 70 Roadmaster Tires

The 1955 Buick 70 Roadmaster uses an 800-15 tire size. That is a numeric bias-ply fitment sized for a 15-inch rim, and it is the primary starting point for replacing tires on the covered Roadmaster application.

Since there is one main size to work from, the next step is choosing how you want the car to look and drive. Staying with 800-15 bias-ply keeps the original size format, while radial equivalents can also be considered. It is still smart to confirm the actual wheel setup on the car, especially if it has been modified over the years.

The primary tire fitment for a 1955 Buick 70 Roadmaster is built around a 15-inch rim. The 800-15 tire size and the available products in that size both align with a 15-inch wheel diameter.

Wheel diameter is only part of the fitment picture, so it also helps to verify wheel width before making a final choice. The available 800-15 bias-ply products are built for 6.00- to 6.50-inch rim widths, while the radial-equivalent group references a 6- to 8-inch range. Actual wheels on collector cars are not always original, so a quick measurement avoids surprises.

Yes. The covered 1955 Buick 70 Roadmaster 8 Cyl. uses the same 800-15 bias-ply tire size. There is no separate primary size within this listed sub-model fitment, so selection does not depend on choosing among multiple Roadmaster tire sizes.

That consistency makes the buying decision simpler because the focus shifts from fitment identification to tire style and construction. On this Buick, the meaningful choices are whether to keep the traditional bias-ply format, whether to consider a radial equivalent, and which whitewall treatment best suits the car’s restoration or touring presentation.

For the 1955 Buick 70 Roadmaster, 800-15 is the primary bias-ply tire size. It uses the vintage numeric sizing format common to American cars of the period, with the 15 indicating rim diameter and the 800 designating the nominal width class.

That matters because a bias-ply 800-15 preserves the traditional construction type associated with the original size format. Owners who want the vintage appearance and feel usually start there, while owners considering more modern road manners often look at radial equivalents instead. Either way, the wheel size and actual wheel width on the car should be confirmed before making a change.

Radial equivalents for 800-15 include 225R15, P235/75R15, P235/70R15, and 800R15. Those choices cover an 80-series metric radial, a 75-series P-metric radial, a lower-profile 70-series P-metric radial, and a bias-look radial that keeps a more traditional visual presentation.

Each of those alternatives should be treated as a comparison point rather than an automatic replacement. The recommended rim-width range for the equivalent group is 6 to 8 inches, and the actual choice should be checked against the Buick’s wheel width, overall tire dimensions, and available fender and steering clearance before switching construction.

Start by confirming wheel diameter, wheel width, and the exact radial size being considered from the 800-15 equivalent group. A radial conversion on a 1955 Buick 70 Roadmaster should also take into account the tire’s overall dimensions, the car’s available clearance, and whether the wheels are still the original type or have been changed.

The practical goal is to avoid assuming that every 15-inch tire will behave the same on a large mid-1950s Buick. Check front steering clearance, rear fender room, and suspension condition, especially on a car that has seen decades of maintenance or modification. Matching the tire choice to the car’s intended use and visual goals usually leads to a better result than choosing by size alone.

The first consideration is staying with the correct 800-15 primary size for the 1955 Buick 70 Roadmaster. From there, the decision usually comes down to keeping bias-ply construction for a traditional presentation or comparing one of the available radial equivalents if the car’s driving use points in that direction.

Appearance matters just as much on a Roadmaster, so whitewall treatment deserves real attention. Wheel width should also be checked before final selection, since available 800-15 bias-ply products are matched to a 6.00- to 6.50-inch rim width. The best choice is the one that matches the Buick’s current wheel setup, visual goal, and planned road use.

The available 800-15 products for the 1955 Buick 70 Roadmaster use wide whitewall styling. Within that sidewall treatment, the main visible difference is whitewall width, with 3.00-inch and 2.50-inch whitewall versions available in the same Coker Classic bias-ply series.

That choice can noticeably change the car’s presence, especially on a large mid-1950s Buick where the tire and wheel opening are visually prominent. A broader whitewall often gives a fuller period-style appearance, while a slightly narrower whitewall can create a more restrained look. Owners focused on exact restoration details should compare their choice against trusted Buick-specific reference material.

The available 800-15 choices for a 1955 Buick 70 Roadmaster are closely related in construction and series, so the main point of comparison is appearance. Both are Coker Classic bias-ply tires with wide whitewalls, and the most visible distinction is whether the car looks better with a 3.00-inch or 2.50-inch whitewall.

Selection becomes easier once the Buick’s purpose is clear. A restoration-oriented car may lean toward the whitewall look that best matches its era presentation, while a regularly driven collector car owner may also be comparing those bias-ply options against radial equivalents. Checking the wheel width on the car remains worthwhile even when the size itself is already settled.

For a period-style 1955 Buick 70 Roadmaster, the natural starting point is the primary 800-15 bias-ply size. That preserves the original size format and supports the broad visual character expected on a big mid-1950s Buick, especially when paired with a wide whitewall sidewall treatment.

The final choice usually comes down to how closely the car is being restored and how it will be used. A bias-ply tire keeps the traditional construction story intact, while a bias-look radial may appeal to owners balancing vintage appearance with a radial format. When exact originality matters, Buick-specific historical references are worth consulting before choosing whitewall width.

Tire construction affects more than ride and handling on a restored 1955 Buick 70 Roadmaster; it also changes how the car presents visually. An 800-15 bias-ply keeps the vintage numeric size format and traditional sidewall character that many restorers associate with a mid-1950s American luxury car.

A radial can still work visually, especially if a bias-look radial is chosen, but the owner should think about the overall presentation rather than construction in isolation. Whitewall width, wheel design, and ride height all influence the final result. On a car with this much presence, the tire needs to support the restoration’s visual intent as well as its road use.

Yes. Modifications can affect tire fitment on a 1955 Buick 70 Roadmaster even when the tire size itself is correct on paper. Aftermarket wheels, different wheel widths, suspension changes, lowered ride height, or body work can all change how an 800-15 or its radial equivalent sits in the wheel opening.

A large collector Buick often has a long service history, so it is wise to inspect the actual setup before choosing tires. Check wheel diameter and width first, then look at steering clearance, fender room, and rear suspension travel. Those steps are especially important before moving from the original bias-ply format to any radial-equivalent size.

Before driving a 1955 Buick 70 Roadmaster on new tires, inspect the wheels, valve stems, lug hardware, and overall wheel condition, then confirm that the tires are inflated properly for their intended use. It also helps to check alignment and basic suspension condition so the new tires are not immediately affected by worn components.

A short shakedown drive is a sensible next step, especially on a collector car that may have spent long periods parked. Listen for rubbing during turns, look for any sign of uneven clearance, and recheck air pressure after the first drive. On an older Buick, the tire installation is only part of road readiness; the rest of the chassis should support it.

Collector-car tires in 800-15 size should be inspected regularly even if the 1955 Buick 70 Roadmaster is driven only occasionally. Watch for sidewall cracking, cuts, bulges, uneven wear, and slow air loss, and keep the tires clean and properly inflated so the car is not resting on underinflated sidewalls during storage.

Storage conditions make a real difference on a low-use vehicle of this age. Keeping the Buick away from prolonged sunlight, excess heat, moisture, and ozone sources helps preserve the tires between drives. It is also smart to move the car periodically or use storage practices that reduce flat spotting, then check pressure and condition again before road use.