1930 Gardner came from one of St. Louis’ best-regarded independent luxury makes, built for buyers who wanted engineering quality and understated prestige in the last years before many smaller American marques disappeared. That year’s Gardner lineup spanned the 136 & 140, the larger 150 Series, and the D Sedan & Phaeton, and tire sizing was not uniform across the range. Eight distinct sizes appear across three model groups, and the choice is tied first to identifying the correct model and wheel diameter rather than weighing bias-ply against radial construction, since every listed fitment is bias-ply. Before choosing a tire, confirm your exact model and the size already fitted to the car.
Which Tire Size Is Right for Your 1930 Gardner
Eight tire sizes are used across 1930 Gardner vehicles, and they vary by model rather than being shared across the full lineup. The real first step is confirming which Gardner model you have and whether it uses an 18-inch or 19-inch rim, because every listed option is a bias-ply fitment but the sizes are not interchangeable across the range. Understanding that distinction before choosing a product saves time and helps match the tire to the correct car.
Year(s): 1930|Fit(s): 136 & 140|Construction: Bias Ply|Rim: 19-in rim
29X5.50 is an antique diameter-by-section size, with a nominal 29-inch overall diameter and 5.50-inch section width rather than a modern width-to-rim code, and it is a bias-ply fitment. This size is specific to the 1930 Gardner 136 & 140 rather than universal across the year and make. It suits restorations aiming to stay with an earlier-era dimensional style used on those models.
Year(s): 1930|Fit(s): 136 & 140|Construction: Bias Ply|Rim: 19 in
550-19 is a numeric bias-ply size in which 5.50 is the nominal section width and 19 is the wheel diameter in inches. BFGoodrich offers this size in Blackwall and Wide Whitewall styles, with a 19-inch rim diameter, a 2.50 to 3.00 inch rim width range, and load ratings listed at 1040 pounds at 32 psi. This size is specific to the 1930 Gardner 136 & 140 and is the practical choice for owners who want a supported production size with clear sidewall-style options.
Year(s): 1930|Fit(s): 136 & 140|Construction: Bias Ply|Rim: 18-in rim
28X5.50 is an antique diameter-by-section bias-ply size that uses a nominal 28-inch overall diameter and 5.50-inch section width format rather than a later numeric designation. This size is specific to the 1930 Gardner 136 & 140 and differs from the 19-inch fitments used elsewhere in that model group. It is the kind of size an owner would choose when preserving an earlier dimensional presentation on the correct wheel diameter.
Year(s): 1930|Fit(s): 136 & 140|Construction: Bias Ply|Rim: 18 in
550-18 is a numeric bias-ply size that denotes a nominal 5.50-inch section width on an 18-inch wheel. Available choices include Excelsior, Firestone, and BFGoodrich, with Blackwall, Wide Whitewall, and Double-Whitewall sidewall styles, 18-inch rim diameter fitment, and rim width references from 3.00 inches up to 4.00 inches depending on the product; listed load ratings include 1000 pounds at 32 psi and 1125 pounds at 32 psi. This size is specific to the 1930 Gardner 136 & 140 and gives owners the broadest mix of brand and appearance choices within that model group.
Year(s): 1930|Fit(s): 150 Series|Construction: Bias Ply|Rim: 18-in rim
30X6.20 is an antique diameter-by-section bias-ply size, using a nominal 30-inch overall diameter and 6.20-inch section width format associated with early balloon-era sizing. This size is specific to the 1930 Gardner 150 Series and is not shared with the other Gardner models listed here. It is best suited to owners keeping the larger 150 Series aligned with its original-era sizing character.
Year(s): 1930|Fit(s): 150 Series|Construction: Bias Ply|Rim: 18 in
650-18 is a numeric bias-ply size that indicates a nominal 6.50-inch section width on an 18-inch wheel. Firestone offers this size in Blackwall and Wide Whitewall styles with a 3.25 to 3.50 inch rim width range, and one listed load figure is 1205 pounds at 36 psi. This size is specific to the 1930 Gardner 150 Series and is the more direct production-style option for owners of the larger Gardner chassis.
Year(s): 1930|Fit(s): D Sedan& Phaeton|Construction: Bias Ply|Rim: 19-in rim
29X5.25 is an antique diameter-by-section bias-ply size, using a nominal 29-inch diameter and 5.25-inch section width format common to the period. This size is specific to the 1930 Gardner D Sedan & Phaeton rather than the rest of the Gardner range. It appeals to owners who want to maintain the earlier style of tire designation associated with those body styles.
Year(s): 1930|Fit(s): D Sedan& Phaeton|Construction: Bias Ply|Rim: 19-in rim
5.25-19 is a numeric bias-ply size, with 5.25 as the nominal section width and 19 as the rim diameter in inches. This size is specific to the 1930 Gardner D Sedan & Phaeton and shares the same general wheel diameter family as that model’s antique-format fitment. It is the straightforward choice for owners who have confirmed a 19-inch wheel and want to stay within the proper size family for those models.
Three 1930 Gardner model groups are covered here. Tire size varies by model, so identifying whether you have a 136 & 140, a 150 Series, or a D Sedan & Phaeton matters before choosing a tire, especially because the lineup spans both 18-inch and 19-inch rim fitments. Select your model below to narrow the fitment history and the available tires that match it.
1930 Gardner 136 & 140
The 136 & 140 represented Gardner’s upper-middle and luxury offerings during a period when independent American makes were competing on refinement rather than mass production. These models use both 18-inch and 19-inch rim fitments depending on the tire size, so owners should confirm the wheel already on the car before narrowing to a specific replacement.
The 150 Series sat at the larger end of the 1930 Gardner range and would have been aimed at buyers expecting substantial road presence and traditional luxury-car proportions. Both listed fitments mount on 18-inch rims, with one antique-format size and one numeric balloon-era size tied specifically to this series.
The D Sedan & Phaeton pairing reflects Gardner’s mix of enclosed and open-car body styles during the final classic prewar years, when buyers still expected a formal sedan or a more sporting phaeton on the same basic make platform. These models use 19-inch rim fitments in both antique and numeric size expressions, so the key is confirming which size family matches the car’s present wheel and restoration direction.
Eleven products are available across three tire sizes for 1930 Gardner vehicles. 550-19 includes 2 BFGoodrich bias-ply options in Blackwall and Wide Whitewall, 550-18 includes 4 bias-ply choices from Excelsior, Firestone, and BFGoodrich in Blackwall, Wide Whitewall, and Double-Whitewall, and 650-18 includes 2 Firestone bias-ply options in Blackwall and Wide Whitewall.
These FAQs focus on how 1930 Gardner tire sizes differ by model, how antique-format sizes relate to numeric bias-ply replacements, and what to check for rim width, inner-tube use, sidewall style, and long-term collector-car care.
Size Basics & Fitment
What tire sizes fit 1930 Gardner vehicles?
1930 Gardner vehicles use eight tire sizes across three model groups. The 136 & 140 use 29X5.50, 550-19, 28X5.50, and 550-18; the 150 Series uses 30X6.20 and 650-18; and the D Sedan & Phaeton uses 29X5.25 and 5.25-19. Rim diameters span both 18-inch and 19-inch applications, so there is no single year-wide Gardner tire size.
That means year and make alone are not enough when ordering tires for a 1930 Gardner. Start by identifying the exact model, then confirm whether the car is set up on 18-inch or 19-inch wheels, and finally compare the size already on the car against the correct fitment family. On sizes with current product coverage, rim width guidance includes 2.50 to 3.00 inches for 550-19, 3.00 to 4.00 inches depending on the 550-18 product, and 3.25 to 3.50 inches for 650-18.
What does 29X5.50 mean on a 1930 Gardner tire?
On a 1930 Gardner, 29X5.50 is an antique diameter-by-section size. The first number refers to the tire’s nominal overall diameter in inches, and the second refers to nominal section width in inches. That is different from a later numeric code such as 550-19, where the last number identifies wheel diameter directly.
Antique-format sizing is common on late-1920s and early-1930s cars, especially during the industry’s transition into balloon tires and more standardized numeric labels. If your 1930 Gardner 136 & 140 wears a 29X5.50-style fitment, treat it as a period-correct sizing language rather than trying to translate it casually into a modern radial equivalent. Matching the original size family and wheel diameter matters more than chasing a modern-looking code.
What does 550-18 mean on a 1930 Gardner tire?
On a 1930 Gardner, 550-18 is a numeric bias-ply size. The 5.50 indicates nominal section width in inches, while 18 indicates the wheel diameter in inches. It is not a metric radial size, and it does not carry the same construction assumptions as a later P-metric or Euro-metric tire.
That matters because a 550-18 tire for a 1930 Gardner 136 & 140 is tied to an 18-inch wheel and to the handling character of a bias-ply tire. Within this size, sidewall appearance varies from Blackwall to Wide Whitewall and Double-Whitewall, and rim-width guidance changes by product from about 3.00 inches up to 4.00 inches. Confirm the actual wheel before choosing among those appearance and brand options.
Do all 1930 Gardner models use the same tire size?
No, 1930 Gardner models do not use the same tire size. The 136 & 140, 150 Series, and D Sedan & Phaeton each have their own fitment group, and the listed sizes are model-specific rather than shared across the full Gardner range. Some models also span more than one rim diameter, which adds another layer of verification.
A buyer comparing only by year and make can easily end up in the wrong size family, especially when both antique-format and numeric bias-ply sizes appear in the same year. The safest path is to identify the exact model first, then compare the tire size stamped on the current tire or confirmed by restoration records. That approach keeps the search focused and avoids mixing an 18-inch fitment into a 19-inch application or vice versa.
Buying the Right Tire
What sidewall styles are available for 1930 Gardner tires?
1930 Gardner tire choices include several sidewall styles, but they vary by size. The 550-19 size is available in Blackwall and Wide Whitewall, the 550-18 size adds Blackwall, Wide Whitewall, and Double-Whitewall options, and the 650-18 size is offered in Blackwall and Wide Whitewall. All currently listed choices are bias-ply tires, so the visual choice is mostly about restoration character rather than switching to a different construction type.
For a 1930 Gardner, sidewall style can noticeably change the car’s period presentation. Blackwalls generally suit a more restrained or utilitarian appearance, while whitewalls bring a more formal, upscale late-classic look that many owners prefer on luxury-era American cars. If the car is being judged, check the expectations of your Gardner club or event, because sidewall treatment can matter nearly as much as the size itself.
What brands make tires for 1930 Gardner vehicles?
Current 1930 Gardner tire coverage includes BFGoodrich, Firestone, and Excelsior, depending on size. BFGoodrich appears in 550-19 and 550-18, Firestone appears in 550-18 and 650-18, and Excelsior appears in 550-18. Brand choice is therefore tied directly to the size and model rather than being available across every Gardner fitment.
That size-specific brand availability matters when you are balancing restoration appearance and product selection. A 1930 Gardner 150 Series, for example, has Firestone offerings in 650-18, while a 136 & 140 on 550-18 opens the door to multiple brands and more sidewall-style variety. It is smart to settle the correct size first, then compare brand presentation, rim-width suitability, and sidewall treatment within that size.
What is the difference between Firestone and BFGoodrich 550-18 tires for 1930 Gardner vehicles?
For 1930 Gardner vehicles using 550-18, Firestone and BFGoodrich differ mainly in sidewall treatment, stated rim width, weight, and listed load figure. Firestone appears in Blackwall and 3.25-inch Double Whitewall versions with a 3.25-inch rim reference and a listed load rating of 1125 pounds at 32 psi, while BFGoodrich appears as a 3.00-inch Whitewall with a 3.00-inch rim reference and a listed load rating of 1000 pounds at 32 psi.
Those details help narrow the right tire once size is settled. Owners who want a particular whitewall width or a brand-specific visual style may lean one way, while owners trying to match an existing wheel more closely should compare the rim-width guidance carefully. Since both are bias-ply 550-18 tires for the same 1930 Gardner fitment family, the decision is usually about presentation and wheel compatibility rather than changing the basic character of the car.
Fitting & Setup
What rim width do 1930 Gardner tires require?
Rim width guidance is available for several 1930 Gardner sizes that have current product coverage. The 550-19 tires fit 19-inch rims with a 2.50 to 3.00 inch rim width range, 550-18 tires reference rim widths from 3.00 inches to 4.00 inches depending on the product, and 650-18 tires fit 18-inch rims with a 3.25 to 3.50 inch rim width range. Those figures are size- and product-specific rather than universal across the Gardner line.
Use those ranges as a wheel check before choosing a tire, especially on a car that may have had wheels changed during an older restoration. A 1930 Gardner that matches the correct tire size but wears the wrong rim width can still create fitment problems, sidewall distortion, or an off-looking stance. Measure the actual wheel or verify it through restoration records instead of assuming all 18-inch or all 19-inch Gardner wheels are the same.
Do 1930 Gardner tires require inner tubes?
1930 Gardner tires fall squarely into the early-1930s bias-ply era, and the listed products do not show tubeless markings. On collector cars of this age, tube-type fitment is the normal expectation, particularly when using original-style wheels. The important point is to match the tube choice to the exact tire size and wheel condition rather than treating tubes as interchangeable accessories.
Inner-tube selection is worth planning at the same time as the tire because an original wheel, aging valve hole, or rough inner rim surface can affect long-term reliability. If your 1930 Gardner still uses original or restored wire or steel wheels, inspect the wheel interior carefully and confirm the valve stem style that belongs with your setup. A proper tube-and-rim combination often matters as much as the tire itself on prewar cars.
Maintenance, Storage & Longevity
How should I store a 1930 Gardner when the tires are fitted?
A 1930 Gardner should be stored in a cool, dry, dark space away from direct sunlight, electric motors, battery chargers, welders, and other ozone-producing equipment that can age rubber. Bias-ply tires also benefit from being kept at proper inflation during storage, because underinflation and long static periods can encourage flat-spotting and sidewall stress more quickly than many modern collector-car owners expect.
If the car will sit for extended periods, move it occasionally to change the contact patch or place it on stands in a way that supports the car safely and preserves the suspension. Clean, dry floors are better than damp earth or bare surfaces that trap moisture. A 1930 Gardner stored thoughtfully will usually keep its tires looking and behaving better than one simply parked and forgotten through seasonal changes.
How long do tires on a 1930 Gardner typically last?
Tires on a 1930 Gardner should be judged more by age and condition than by mileage. Collector cars often accumulate few miles, yet rubber can still harden, crack, or weaken internally over time. A practical rule is to begin evaluating tires closely once they are around five to seven years old and to treat about ten years as the point where replacement deserves serious consideration regardless of tread depth.
Check the manufacturing date and inspect the tire for sidewall cracking, weathering, irregular wear, or persistent loss of pressure. A low-mileage 1930 Gardner that only sees parades, tours, or weekend drives can still end up riding on aged rubber that looks better than it really is. When in doubt, age is a more important signal than appearance alone on a prewar collector car.
How often should tires on a 1930 Gardner be inspected?
Tires on a 1930 Gardner should be inspected before every drive and again before any longer outing or tour. Look for sidewall cracking, tread separation, uneven wear, embedded debris, cuts, bulges, and signs that the tire is no longer holding pressure consistently. On tube-type setups, valve stems and tube condition deserve the same attention as the outer casing.
Frequent inspection is especially important on prewar cars because long periods of storage can hide problems until the next road outing. A quick check in the garage is useful, but a hands-on inspection with inflation confirmed at operating pressure is better. If the spare is part of your touring plan, inspect it too, since many collector cars carry a spare that has aged out without obvious visible wear.
Restoration & Authenticity
What tires were originally fitted to the 1930 Gardner 136 & 140?
A 1930 Gardner 136 & 140 would have originally used bias-ply tires, because that was the standard construction for American passenger cars in 1930. Within that model group, both antique-format sizes such as 29X5.50 and 28X5.50 and numeric bias-ply sizes such as 550-19 and 550-18 appear, reflecting the period’s transition in tire size conventions rather than a move to modern construction.
For an accurate restoration, focus first on matching the correct size family and wheel diameter for your specific car, then choose the sidewall treatment that suits the car’s intended market presentation or judging standard. Original-equipment brand assumptions are best avoided unless your individual Gardner’s history confirms them. Marque clubs, period sales literature, and survivor cars are the right next step when you want trim- or body-specific authenticity.
Does correct tire fitment matter for showing a 1930 Gardner?
Correct tire fitment matters a great deal when showing a 1930 Gardner because judges and knowledgeable enthusiasts often notice size family, construction type, and sidewall style immediately. A prewar Gardner shown for authenticity is expected to wear bias-ply tires in the proper size range for its model, and a visibly incorrect wheel diameter or an out-of-period sidewall treatment can stand out even to casual observers.
The practical standard is to match the model-specific size first, then choose a sidewall style that aligns with the car’s restoration goal. A 136 & 140 on the wrong 18-inch versus 19-inch fitment, or a D Sedan & Phaeton wearing an obviously mismatched size family, can undermine an otherwise careful restoration. Event rules vary, so consult Gardner and prewar judging resources before finalizing the tire appearance.
What is the difference between Firestone Balloon and other 1930 Gardner tire options for the 150 Series?
On the 1930 Gardner 150 Series, the currently listed production-style option is Firestone Balloon in 650-18, available in both Blackwall and 3.50-inch Whitewall form. The Blackwall version lists a maximum load capacity of 1205 pounds at 36 psi, and both versions fit 18-inch rims with a 3.25 to 3.50 inch rim width range. That makes the choice within this size more about appearance than about switching size families.
Compared with the antique-format 30X6.20 fitment used on the same 150 Series, 650-18 presents a more standardized numeric balloon-era expression while staying within correct bias-ply practice. Owners choosing between them are usually deciding how closely to mirror period labeling and visual style on the car. If the Gardner is being restored for authenticity, compare the wheel and the car’s established history before settling on one presentation.
Safety & Road Use
Are 1930 Gardner tires safe for highway driving?
1930 Gardner tires can be suitable for normal road use when they are the correct size, in sound condition, and fitted to the proper wheels, but they remain early-style bias-ply tires with the driving manners of the period. No speed ratings are listed for the available 550-19, 550-18, or 650-18 products here, so the sensible approach is to drive within the tire maker’s intended use and within the mechanical limits of a 1930 luxury car.
A well-sorted 1930 Gardner is usually limited more by age-era brakes, steering, suspension, and road conditions than by any desire to cruise like a modern car. Keep speeds reasonable, allow longer stopping distances, and avoid treating a prewar bias-ply setup like a modern radial touring tire. Highway use is less about chasing the posted speed limit and more about maintaining stability, condition, and margin.
What inflation pressure should I use for 1930 Gardner tires?
Inflation pressure on a 1930 Gardner should follow the factory recommendation for the car when available, while also respecting the pressure associated with the specific reproduction tire you choose. Among current listings, 550-19 appears with 1040 pounds at 32 psi, 550-18 appears with figures including 1000 pounds at 32 psi and 1125 pounds at 32 psi, and 650-18 appears with 1205 pounds at 36 psi. Those are tire-specific ratings, not universal Gardner inflation settings.
Use the correct size first, then compare the tire maker’s published load-and-pressure information with the car’s original guidance before setting operating pressure. Do not transfer a 650-18 pressure figure to a 550-18 tire, and do not assume one brand’s 550-18 recommendation automatically applies to another brand’s version. Pressure affects ride, wear, steering effort, and casing shape on a bias-ply tire more than many owners realize.
What should I check before taking a 1930 Gardner on a longer drive?
Before a longer drive in a 1930 Gardner, inspect every tire for cracking, cuts, bulges, unusual wear, and secure inflation, and include the spare in the same check. If the car runs tube-type tires, inspect the valve stems and look for any sign of seepage or damage around the stem base. Wheel condition matters too, especially on older restored rims that may have seen decades of service.
Tires are only one part of a broader pre-drive routine on a prewar car, so combine that inspection with checks of brakes, steering play, wheel-bearing condition, and fluid levels. A short local test drive before a tour is often the best way to catch vibration, pull, or heat-related issues while still close to home. The goal is not just getting the 1930 Gardner moving, but keeping it dependable over the whole route.
