The 1930 Auburn 85 Series comes from an era when American cars balanced prestige, style, and touring comfort with increasingly capable road manners. Auburn models of this period remain especially appealing to collectors who want a car that looks authentically prewar without losing its strong mechanical character. Tire selection for the 1930 Auburn 85 Series centers on two period bias-ply size expressions, 28X5.50 and 550-18, both tied to the car’s 18-inch wheel fitment. Available choices include traditional blackwall and whitewall presentations across several vintage tire series. The key is matching the tire to the car’s wheel setup and restoration goals while preserving the right prewar look and road-going proportions.
Which Tire Size Is Right for The 1930 Auburn 85 Series
The 1930 Auburn 85 Series uses two primary tire size expressions, both in bias-ply construction and both associated with 18-inch wheel fitment. Since the covered sub-model shares these sizes, the real decision is less about model variation and more about understanding the size notation, confirming the actual wheel on the car, and choosing the sidewall style and tire series that best suits a road car or restoration-minded presentation.
The size 28X5.50 uses an older diameter-by-section format, where 28 refers to the tire’s approximate overall diameter and 5.50 refers to its nominal section width in inches. It is a bias-ply fitment that reflects the sizing language common to late 1920s and early 1930s automobiles such as the Auburn 85 Series. This size matters most to owners trying to interpret original-era tire markings or compare period literature with modern product listings. Before choosing it, confirm that the wheel and the tire marking on the car align with this older format rather than a later numeric expression.
The size 550-18 is a numeric bias-ply format, with 5.50 representing the nominal tire section width in inches and 18 identifying the wheel diameter. On the 1930 Auburn 85 Series, this is the most product-supported fitment, with period-style bias-ply choices from Excelsior, Firestone, BFGoodrich, and Michelin. Sidewall treatments include blackwall, wide whitewall, and double-whitewall across series such as Comp H, Firestone Classic Bias Ply, Silvertown Classic Bias Ply, and Double Rivet. It is the practical size to evaluate when appearance, available brand choice, and wheel-width compatibility all matter to the finished result.
Tire fitment is straightforward for the covered 1930 Auburn 85 Series sub-model, since the same primary sizes apply throughout it. Checking the exact sub-model still helps confirm that the car remains on its expected wheel setup before comparing sidewall and product choices.
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1930 Auburn 85 Series 6 Cyl.
The 1930 Auburn 85 Series 6 Cyl. uses the same period bias-ply fitment family found on this model line, centered on 28X5.50 and 550-18 sizing. That gives the owner room to focus on wheel confirmation, period-style appearance, and whether a blackwall, whitewall, or double-whitewall presentation best suits the car.
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Best 1930 Auburn 85 Series Tires for Sale
Available 550-18 choices span Excelsior, Firestone, BFGoodrich, and Michelin, with differences in tire series, sidewall treatment, and rim-width specifications. Blackwall, wide whitewall, and double-whitewall options make appearance an important part of the final selection.
Owners of a 1930 Auburn 85 Series usually need clear answers on size notation, 18-inch wheel fitment, bias-ply construction, sidewall style, and what to inspect before putting a collector car back on the road.
Tire Size & Fitment
What tire size fits a 1930 Auburn 85 Series?
The 1930 Auburn 85 Series uses two period bias-ply size expressions: 28X5.50 and 550-18. These are closely related vintage sizing formats, and the covered 6-cylinder sub-model uses the same fitment family rather than a separate modern tire size.
The practical step is confirming what is actually mounted on the car now, especially if the wheels or tires were changed during an older restoration. Many owners will shop by 550-18 because that is where the visible product variety appears, but the wheel diameter and the tire’s period sizing convention should both be checked before making a final choice.
What size rim does a 1930 Auburn 85 Series use?
The 1930 Auburn 85 Series uses an 18-inch rim with its primary tire fitment. That rim diameter corresponds directly to the 550-18 size, and it also aligns with the period fitment family represented by 28X5.50.
Wheel diameter should be verified on the car before ordering tires, especially on collector vehicles that may have replacement wheels from an earlier restoration. Rim width matters as well, since available 550-18 products are built around different approved wheel widths, so measuring both diameter and width helps narrow the right tire choices.
What does 28X5.50 mean on a 1930 Auburn 85 Series?
On a 1930 Auburn 85 Series, 28X5.50 is an antique diameter-by-section size marking. The first number refers to the tire’s approximate overall diameter, while 5.50 refers to its nominal section width in inches rather than the wheel diameter.
That older format can be confusing because it does not read like later numeric sizes such as 550-18. If the Auburn is being restored or compared against original-era references, understanding that difference helps prevent ordering by notation alone and encourages checking the actual wheel diameter and the tire markings already on the car.
Choosing the Right Tire
What should I consider when choosing a 550-18 tire for a 1930 Auburn 85 Series?
Start with the correct size, construction, and wheel dimensions. A 550-18 for the 1930 Auburn 85 Series should be a bias-ply tire matched to the car’s 18-inch wheel, and the available products vary in approved rim width, weight, load specification, series, and sidewall presentation.
After size confirmation, the choice usually comes down to how the car will be used and how it should look. A road-driven touring car may prioritize wheel compatibility and load details, while a restoration-oriented car may lean harder on blackwall, wide whitewall, or double-whitewall appearance to better match the car’s intended period presentation.
What sidewall styles are available for 1930 Auburn 85 Series tires?
The available 550-18 tires for a 1930 Auburn 85 Series include blackwall, wide whitewall, and double-whitewall sidewall styles. Those choices can change the car’s visual character significantly even when the overall tire size remains the same.
Blackwall usually gives the most restrained and utilitarian look, while whitewall and double-whitewall treatments create a more formal prewar presentation. Since sidewall appearance is a styling decision rather than a fitment change, the better approach is to confirm the proper size first and then select the sidewall treatment that best matches the car’s restoration direction.
What brands offer tires for the 1930 Auburn 85 Series?
The 1930 Auburn 85 Series has 550-18 tire choices from Excelsior, Firestone, BFGoodrich, and Michelin. Those products also span several series, including Comp H, Firestone Classic Bias Ply, Silvertown Classic Bias Ply, and Double Rivet.
Brand selection is only one part of the decision. It also helps to compare sidewall style, wheel-width compatibility, and any stated load figure where available, since two tires in the same nominal size can still suit different restoration goals or wheel setups. Choosing by complete specification usually leads to a better match than choosing by brand name alone.
Restoration & Appearance
Which tire should I choose for a period-style 1930 Auburn 85 Series?
A period-style 1930 Auburn 85 Series should stay with its proper vintage bias-ply sizing family, centered on 28X5.50 and 550-18. Within that fitment, the more useful decision is which available 550-18 tire best matches the car’s wheel setup and the visual character the restoration is aiming to achieve.
Blackwall, wide whitewall, and double-whitewall options each create a different prewar look, and several vintage tire series are available in the size. If exact historical authenticity matters beyond general period style, compare the car against marque references, restoration photography, and authoritative Auburn-specific sources before deciding on a final sidewall treatment.
Does correct tire fitment matter for a 1930 Auburn 85 Series restoration?
Correct tire fitment matters a great deal on a 1930 Auburn 85 Series because tire diameter, section width, and sidewall presentation all influence how the car sits and how authentic it appears. On a prewar car, an obviously mismatched tire can affect the visual balance as much as it affects usability.
Fitment also shapes practical details such as wheel compatibility and body clearance, especially if the car has older replacement wheels or mixed restoration parts. Staying within the proper 28X5.50 and 550-18 fitment family keeps the search focused, then the final appearance decision can be made around blackwall or whitewall styling.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1930 Auburn 85 Series?
Yes. A 1930 Auburn 85 Series may have had wheel, brake, suspension, or body work performed over many decades, and any of those changes can affect how a vintage tire size sits on the car. Even when 550-18 is the correct primary fitment, the actual wheel setup still deserves verification.
Modified ride height, different wheel widths, or non-original wheel centers can change clearance at the fender, steering components, or suspension. The safest approach is to measure the mounted wheel diameter and width, inspect available space around the existing tires, and compare those conditions before selecting a new bias-ply replacement.
What should I inspect before driving a 1930 Auburn 85 Series on new tires?
Before road use, inspect the wheels, valve stems, lug hardware, and the general condition of the braking and suspension systems. Tire pressure, bead seating, visible sidewall condition, and any interference at full steering lock should also be checked on a 1930 Auburn 85 Series before regular driving resumes.
A collector car that has spent long periods parked deserves extra attention after new tires are installed. Short local test drives can reveal rubbing, vibration, or air-loss issues that are easy to miss in the garage, and a second inspection afterward helps confirm that the tires and wheels are settling in properly.
How should 550-18 tires on a collector 1930 Auburn 85 Series be maintained?
550-18 tires on a collector 1930 Auburn 85 Series should be kept properly inflated, visually inspected often, and protected from long exposure to sunlight, moisture, and ozone sources during storage. Low annual mileage does not stop aging, so condition matters just as much as tread depth on an older bias-ply tire.
Regular checks for cracking, bulges, cuts, flat spotting, and slow air loss are especially important on a prewar car that may sit for extended periods. It also helps to move the car periodically, maintain clean wheel and tire surfaces, and recheck pressure before any longer outing rather than assuming the tires are ready from storage.
