Buick 70 Roadmaster Tires

Buick 70 Roadmaster uses three tire sizes across the years covered here. The 1941, 1946, and 1947 Buick 70 Roadmaster use 700-15 on 15-inch wheels. The 1948 and 1949 Buick 70 Roadmaster use 820-15 on 15-inch wheels. The 1950 through 1958 Buick 70 Roadmaster use 800-15 on 15-inch wheels.

That means the main fitment question is the model year, not a wheel-diameter change. If the car has been restored or modified at some point, confirm the year against the actual wheel and compare the tire already on the car with factory-era references. On a large Buick, even a small change in section width affects stance and clearance, so matching the correct year-range size is the right place to start.

On Buick 70 Roadmaster, 700-15 is an older numeric bias-ply size. The 700 portion indicates a nominal section width of about 7.00 inches, and the 15 indicates the wheel diameter in inches. The available 700-15 products for Buick 70 Roadmaster are bias-ply tires built for 15-inch rims, with many listed for 5.00 to 5.50 inch rim widths.

That size belongs to the earliest years in this Roadmaster group, specifically 1941 and 1946–1947. Buyers often read numeric sizes as if they were modern metric tires, but they are not directly comparable in shape or sidewall profile. If your goal is period appearance and proper proportions on an early Buick 70 Roadmaster, stay with the correct numeric bias-ply size rather than substituting a later Roadmaster size without checking clearance and overall look.

Buick 70 Roadmaster uses 15-inch wheels throughout the 1941 and 1946–1958 range covered here. The listed 700-15, 820-15, and 800-15 tire sizes all correspond to a 15-inch rim diameter. What changes across the years is the tire size itself, especially the nominal section width, not the basic wheel diameter.

That simplifies one major part of fitment, but it does not mean every 15-inch tire is interchangeable. Different Roadmaster years use different numeric sizes, and the listed rim width ranges also vary by tire size and application. Before fitting a new set, verify the wheel diameter stamped on the wheel or measure it correctly at the bead seat, then choose the year-correct size rather than selecting by rim diameter alone.

Buick 70 Roadmaster is shown here with bias-ply tires in older numeric sizes, and tube-type construction is common within these offerings. For 700-15, 820-15, and 800-15 bias-ply fitments, a tube is required unless a tire is specifically identified otherwise. One 700-15 military-style product is listed as tubeless, but that does not change the general tube requirement for the period-correct passenger bias-ply selections.

On a collector car, tube choice matters almost as much as the tire itself. Use tubes that match the tire size and valve stem arrangement, and inspect the wheel carefully for rust, pitting, or damage before assembly. If the car has replacement wheels or non-passenger applications fitted in the past, confirm whether the wheel and tire combination is still appropriate for a Buick 70 Roadmaster passenger-car restoration.

The correct Buick 70 Roadmaster tire size is tied directly to model year. Buick 70 Roadmaster uses 700-15 for 1941 and 1946–1947, 820-15 for 1948–1949, and 800-15 for 1950–1958. All of those sizes fit 15-inch wheels, so the year breakpoints are the most useful guide when identifying the proper tire.

Start with the actual model year on the car, then compare it with the existing wheel and any restoration paperwork. If the car has had wheel changes during its life, use the year listing as your baseline and then verify the wheel dimensions before mounting tires. That approach keeps you from choosing a later or earlier Roadmaster size simply because the wheel diameter happens to match.

Buick 70 Roadmaster tires are available in blackwall, narrow whitewall, and wide whitewall styles across the listed sizes. The 700-15 offerings include blackwall and wide whitewall choices. The 820-15 group has the broadest variety, including blackwall, narrow whitewall, and several wide whitewall widths. The 800-15 selections listed here are both wide whitewall tires.

Sidewall style has a major effect on the look of a Roadmaster, especially on late 1940s and 1950s cars where whitewall width helps define the period appearance. If your Buick 70 Roadmaster is being restored for authenticity, compare the sidewall treatment to period photos, original literature, or marque-club judging standards. If it is a driver, choose the sidewall style that best matches the era you want the car to present.

Buick 70 Roadmaster tires in these sizes are available from Firestone, BFGoodrich, STA, US Royal, Universal Vintage Tire, Avon, and Coker Classic. Not every brand appears in every size, and some brands focus on certain period styles or specialty applications. The broadest brand coverage appears in 820-15, while 800-15 is represented here by Coker Classic.

Brand choice usually comes down to the combination of size, sidewall look, and the style of restoration you are building. Some owners want a familiar American classic brand name, while others care most about whitewall width or a specialty tread style. Once the correct Buick 70 Roadmaster size is established, narrow the choice by appearance, intended use, and whether the tire is a standard passenger bias-ply or a specialty application.

Buick 70 Roadmaster tires here appear in several series, including Firestone Classic Bias Ply, Silvertown Classic Bias Ply, US Royal Classic Bias Ply, Universal Classic Bias Ply, Coker Classic Bias Ply, Turbospeed Mk4, Traxion, Super Transport, Transport Highway, Firestone Classic Military, Dirt Track, and Dragster Cheater. Most are period-style passenger bias-ply lines, while others are military, truck, racing, or specialty-purpose tires. That means the series name often tells you as much about intended use as the size itself.

For a typical Buick 70 Roadmaster restoration or road car, the passenger-car classic bias-ply series are usually the most appropriate place to focus. Military and truck series can share the same size but have a different appearance and intended duty, while racing series are aimed at specialized use. Read the series name as a clue to the tire’s character, then match it to how your Roadmaster will actually be presented and driven.

A stored Buick 70 Roadmaster should be kept in a cool, dry, dark space away from direct sunlight, ozone sources, and wide temperature swings. Clean tires last better when they are free of petroleum residue, harsh dressings, and standing moisture. Bias-ply collector tires also benefit from keeping the car on a smooth surface and avoiding long periods with one part of the casing bearing all the weight in the same spot.

If the Buick 70 Roadmaster will sit for extended periods, move it occasionally or support it in a way that reduces flat-spotting and stress on the sidewalls. Keep inflation checked even during storage, because underinflation can damage a low-use collector tire as surely as regular driving can. A careful storage routine helps preserve both the appearance and service life of period-style tires.

Tires on a Buick 70 Roadmaster should be inspected before every meaningful drive and more thoroughly several times through the year. Check inflation, tread condition, sidewall cracking, valve stems, and any signs of rubbing, impact damage, or age-related separation. On a heavy full-size Buick, small issues can become noticeable quickly because the car places real load on its tires even in occasional hobby use.

Collector cars often spend more time parked than driven, which means age and environment can matter more than tread wear. Include the spare in your inspection routine, and look closely after winter storage or after the car has been sitting for long periods. If anything looks uneven from one corner to the next, inspect the wheel, alignment, suspension, and brake condition before putting more miles on the Buick 70 Roadmaster.

Buick 70 Roadmaster tires should be replaced when age, cracking, hardening, bulges, vibration, casing damage, or repeated air loss suggest the tire is no longer sound, even if the tread still looks deep. Collector tires often age out before they wear out. That is especially true on a car that is driven infrequently but stored for long periods between outings.

Treat appearance as only one part of the decision. A tire that still looks attractive can be past its useful service life, particularly on a large, heavy car like Buick 70 Roadmaster. When in doubt, have the tires and tubes evaluated by a specialist familiar with vintage bias-ply construction and collector-car use rather than relying on tread depth alone.

Buick 70 Roadmaster originally used different numeric 15-inch tire sizes over this production span rather than one single fitment for every year. The year groups covered here are 700-15 for 1941 and 1946–1947, 820-15 for 1948–1949, and 800-15 for 1950–1958. The available replacement lines are period-style bias-ply series from several brands, but the exact original brand and sidewall treatment can vary by year and presentation.

For a restoration aiming at factory accuracy, start with the correct size for the car’s exact year and then confirm brand appearance and whitewall style against original literature or marque-club references. Buick 70 Roadmaster spans a period when styling changed quickly, and tire presentation changed with it. Getting the size right first keeps the car’s stance and proportions in line before you fine-tune the cosmetic details.

Correct tire fitment can absolutely affect how a Buick 70 Roadmaster is judged and how complete the restoration appears. Judges and knowledgeable enthusiasts notice whether the tire size, sidewall treatment, and overall profile suit the year of the car. On a prominent full-size model like Buick 70 Roadmaster, the tire’s shape and whitewall presentation are a major part of the car’s visual balance.

A Roadmaster wearing the wrong size can sit too narrow, too tall, or too heavy in profile even if the wheel diameter is correct. For show-oriented restorations, compare your choice against period photos, sales literature, and marque-club guidance. For driver-level restorations, choosing the year-correct size and a believable sidewall style will usually do more for the car’s authenticity than chasing small cosmetic details elsewhere.

Buick 70 Roadmaster tires are offered here in blackwall, narrow whitewall, and wide whitewall styles, depending on size. Blackwall can suit more restrained presentations, while the postwar Roadmaster is especially at home with whitewall treatment. The 820-15 size used in 1948–1949 has the broadest variety of whitewall widths in these offerings, and the 800-15 options listed for 1950–1958 are both wide whitewall tires.

The correct choice depends on the exact year and the character of the restoration. A conservative touring look may point toward blackwall or a narrower whitewall, while a fully dressed Buick 70 Roadmaster often looks most convincing with a period-appropriate wide whitewall. Study original photos of cars trimmed like yours, because sidewall width can change the visual era of the car more than many owners expect.

Buick 70 Roadmaster can be driven on public roads with properly selected, properly mounted, and properly maintained tires that match the car’s year and intended use. The listed passenger options are bias-ply collector tires, and some specialty products in the same sizes are meant for military, truck, or racing use rather than normal road service. Safety starts with using the correct size and the appropriate type of tire for the way the car will be driven.

A Roadmaster is a large, substantial car, so tire condition, inflation, and balance matter greatly to stability and braking feel. Before any regular road use, inspect the complete chassis, wheels, tubes, and brake system, not just the tread. Public-road driving is reasonable only when the whole car is sorted as a system and the tires chosen are appropriate for normal collector-car operation.

Before driving a Buick 70 Roadmaster, check tire pressure, visible sidewall condition, tread, valve stems, wheel fasteners, and whether the tires match correctly from side to side on each axle. Also inspect for flat spotting after storage and look for any signs of tube or bead leakage. Because Buick 70 Roadmaster uses bias-ply tires here, even a car that looks fine at rest can reveal vibration or pull once it is moving.

Give the car a cautious first few miles after storage and pay attention to steering response, brake pull, and unusual noise. If the tires are newly fitted, recheck pressures and wheel security after the initial outing. A deliberate pre-drive routine is especially important on a collector Buick 70 Roadmaster because many problems show up from inactivity rather than from heavy mileage.

Buick 70 Roadmaster on period-style bias-ply tires should be driven at sensible, conservative speeds that respect both the age of the car and the behavior of bias-ply construction. Even when new, these tires do not feel like modern radials, and the car’s steering, suspension, and braking were designed in a different era. Smooth inputs and moderate cruising are much more in character than sustained high-speed driving.

Choose a pace that leaves plenty of margin for braking distance, road crown, and heat buildup, especially in warm weather or on long runs. If the car wanders, vibrates, or feels unsettled, address the mechanical condition before asking more of it. Buick 70 Roadmaster is happiest when driven as a well-kept vintage road car, not as a modern highway car on modern tire expectations.