1933 Nash Tire Fitment Guide

1933 Nash vehicles use four different tire sizes across five models. The 1120 and 1130 use 550-17, the 1170 uses 550-18, the 1180 uses 6.50-17, and the Ambassador uses 700-18. That means the 1933 Nash line is split between 17-inch and 18-inch wheel diameters rather than sharing one universal fitment. Published rim width guidance appears with some products: 550-18 products are listed for 3.00-inch, 3.25-inch, and 4.00-inch rims depending on product, while 700-18 products are listed for 3.75- to 4.00-inch rims.

The practical takeaway is that year and make alone are not enough for a 1933 Nash tire decision. Start by confirming whether you have a 1120, 1130, 1170, 1180, or Ambassador, then verify whether the car uses a 17-inch or 18-inch wheel. Once that is settled, you can compare the available bias-ply products and sidewall looks in the correct size instead of trying to force interchange across different Nash series.

On a 1933 Nash tire, 550-17 is an early numeric bias-ply size. The 5.50 portion refers to the nominal section width, while 17 identifies the wheel diameter in inches. It is not a modern metric size, and it does not follow the later alphanumeric or radial naming systems that became common decades afterward. Within the 1933 Nash range, 550-17 applies to the 1120 and 1130.

That size code matters because it points you toward the correct family of prewar tires rather than a modern substitute with different proportions. If you own a 1933 Nash 1120 or 1130, staying with 550-17 preserves the visual balance those smaller Nash models were designed around. From there, your next decision is usually sidewall style, since blackwall, double-whitewall, and wide whitewall versions are all available within that same basic size.

No, 1933 Nash models do not all use the same tire size. The 1120 and 1130 share 550-17, but the 1170 uses 550-18, the 1180 uses 6.50-17, and the Ambassador uses 700-18. Even where two sizes share a 17-inch rim or an 18-inch rim, the tire width and overall proportions differ enough that they should not be treated as one interchangeable fitment across the whole make.

That variation reflects Nash's broad lineup in 1933, from more modest series cars to the larger Ambassador. If you are unsure which model you own, check the body and chassis identification before choosing a tire. Sorting that out first will narrow your search quickly and keep you from comparing products built for a different series with a different stance, load profile, and wheel diameter.

1933 Nash tires are available in several sidewall styles depending on size. The 550-17 size offers blackwall, double-whitewall, and wide whitewall versions from BFGoodrich. The 550-18 size also appears in blackwall, double-whitewall, and wide whitewall form, while 700-18 follows the same pattern with Firestone offerings. Those options let owners tune the visual character of a 1933 Nash without changing away from a bias-ply construction.

For a strictly early-1930s appearance, blackwall often gives the most restrained period look, while whitewall treatments add a more formal or upscale presentation that many restorers prefer on larger and dressier cars. The right choice depends on how your 1933 Nash is being finished and shown. If appearance matters as much as fitment, compare the sidewall style to the car's trim level, body style, and intended restoration theme before settling on one option.

Three brands appear across the current 1933 Nash tire range: BFGoodrich, Firestone, and Excelsior. BFGoodrich covers 550-17 and also appears in 550-18, Firestone appears in 550-18 and 700-18, and Excelsior is represented in 550-18. All of them are offered in bias-ply construction, which matches the prewar character of the 1933 Nash lineup rather than introducing a modern radial format into these listed fitments.

Brand choice for a 1933 Nash usually comes down to the exact size you need and the sidewall treatment you want to see on the car. Some sizes have only one brand represented, while others give you a broader mix of names and appearances to work with. Once the correct size is established, compare brand availability within that size instead of assuming every brand makes every fitment across the full 1933 Nash range.

Within the 550-18 fitment for 1933 Nash vehicles, Firestone and BFGoodrich differ in both sidewall offerings and published specifications. Firestone appears in blackwall and double-whitewall forms with a listed maximum load of 1125 pounds at 32 psi and a 3.25-inch rim width. BFGoodrich appears as a wide whitewall with a listed maximum load of 1000 pounds at 32 psi and a 3.00-inch rim width. Both remain bias-ply tires intended for the same 18-inch wheel diameter.

That means the decision is less about basic fitment than about the combination of sidewall appearance and published specs that best matches your 1933 Nash 1170. If you want a Firestone look or need the listed 3.25-inch rim pairing, the Firestone choices stand apart. If you prefer a BFGoodrich wide whitewall presentation, that option brings a different visual treatment within the same overall size family.

Rim width guidance for 1933 Nash tires varies by size and, in some cases, by product. The 550-18 size is listed on products with 3.00-inch, 3.25-inch, and 4.00-inch rim widths, while the 700-18 size is listed for 3.75- to 4.00-inch rims. A 17-inch rim diameter is confirmed for 550-17 and 6.50-17, but published width guidance does not appear across the listed products for those two sizes.

The safest approach is to confirm the actual wheel on your 1933 Nash before selecting a tire, especially if the car has had wheels swapped over the years. Matching the tire to the correct rim width helps preserve the proper section shape and stance. On a prewar car, even a correct nominal tire size can behave differently if the wheel is narrower or wider than the tire was designed to support.

Original 1933 Nash wheels cannot be treated as universal across all listed tire sizes because the range includes both 17-inch and 18-inch rim diameters. The 1120, 1130, and 1180 use 17-inch fitments, while the 1170 and Ambassador use 18-inch fitments. That rim diameter difference alone keeps the full 1933 Nash lineup from sharing one wheel-and-tire package across every model.

Even within the same rim diameter, you should still verify the wheel before assuming a different 17-inch or 18-inch Nash tire will be appropriate. A 6.50-17 is not simply a substitute for a 550-17, and a 700-18 is a different fitment class than a 550-18. Keeping the original wheel with the correct model-specific tire size is the best way to preserve both proper fit and the car's intended prewar proportions.

A 1933 Nash should be stored away from direct sunlight, standing water, and ozone sources such as electric motors, battery chargers, and welders. Clean, dry floors and a stable indoor environment help protect the sidewalls and tread from premature aging. Because 1933 Nash fitments here are all bias-ply, long periods of sitting can encourage flat-spotting more readily than many later radial tires. Keeping inflation checked during storage also helps the tire hold its shape.

For a collector car that is not driven often, move the 1933 Nash periodically or support it in a way that reduces prolonged static loading if the car will sit for an extended season. That is especially useful if the car carries larger, heavier prewar tires such as 700-18. Good storage habits preserve ride quality, reduce cosmetic sidewall deterioration, and make the car more pleasant to return to service when driving season comes around.

Tires on a 1933 Nash are usually judged by age and condition more than by mileage, since collector cars often cover relatively few miles each year. A sound rule is to evaluate them closely once they reach the five- to seven-year range, then give serious replacement consideration as they approach about ten years from the date code, even if the tread still looks usable. Visible cracking, persistent flat-spotting, impact damage, or separation concerns can shorten that timeline.

That age-based approach is more realistic for a prewar Nash than waiting for the tread to wear out. Low annual mileage can make old tires seem serviceable long after the rubber has begun to harden. Checking the date code and combining it with regular visual inspection gives you a more accurate picture of whether the tires on your 1933 Nash are still fit for road use.

Tires on a 1933 Nash should be inspected before every drive and again before any extended outing. Look for sidewall cracking, cuts, bulges, uneven tread wear, and any sign that the tire has been losing pressure while parked. Prewar cars also deserve a close look at the valve stems and the spare, since a long-stored spare can age just as much as the tires on the ground even if it has never seen road use.

Frequent inspection matters because a 1933 Nash may spend long intervals parked, and age-related issues often appear before mileage-related ones. A quick walkaround can catch a problem while it is still minor, rather than after the car is already underway. On an older car with bias-ply tires, that routine is one of the simplest ways to make local drives and longer tours more predictable.

A 1933 Nash 1120 used 550-17 tires, and bias-ply construction is the period-correct type for a car from 1933. That fits the broader prewar industry pattern, since radial passenger-car tires were still decades away from normal American use. Within today's offerings, blackwall and whitewall variations exist in that same size, but the underlying construction remains true to the era. Original brand fitment could vary by market and supply, so the size and construction type are usually the first authenticity points to lock down.

For a careful restoration, confirm your 1933 Nash 1120 against factory literature, surviving originals, and Nash marque specialists if you want to settle details beyond the basic size. That is especially helpful when choosing between blackwall and whitewall presentation. Getting the 550-17 size and bias-ply construction right will do more for authenticity than chasing brand assumptions that may have changed from one selling region or production period to another.

Correct tire fitment matters a great deal when showing a 1933 Nash, especially in preservation or judged restoration settings. Size, construction, and sidewall style all affect whether the car presents as era-correct. A 550-17 on a 1120 or 1130, a 550-18 on a 1170, a 6.50-17 on a 1180, and a 700-18 on an Ambassador each support the proper proportions for that specific model. A visibly incorrect sidewall treatment or the wrong tire size can alter the car's stance enough to be noticed immediately.

Judging standards differ by event, so it is worth checking with Nash clubs or the organization overseeing the show before finalizing your tires. Some events focus on overall authenticity, while others are stricter about exact period appearance. If your 1933 Nash is being built for show rather than casual driving, tire choice should be treated as a finishing detail on par with trim, paint character, and wheel presentation.

For the 1933 Nash Ambassador in 700-18, Firestone offers both Balloon and Classic Bias Ply versions. The Firestone Balloon line appears in blackwall, double-whitewall, and wide whitewall styles, each listed at 1520 pounds maximum load at 36 psi and for 3.75- to 4.00-inch rims. The Firestone Classic Bias Ply blackwall in the same size also carries 1520 pounds at 36 psi and the same rim-width range, but it differs in series identity and listed weight from the Balloon versions.

That makes the choice more about visual presentation and series character than basic fitment for a 1933 Nash Ambassador. Owners pursuing a particular prewar look may prefer the Balloon naming and profile association, while others may simply want the blackwall appearance in the same size and load class. Since both are built around the same 700-18 fitment, compare the specific sidewall treatment and product details against the way you want the Ambassador to present.

1933 Nash tires can be suitable for highway driving when they are the correct size, in good condition, and used within their intended limits, but all listed fitments here are bias-ply tires. Bias-ply construction delivers authentic prewar behavior and appearance, yet it does not feel the same as a modern radial in steering response or tracking. No speed ratings are published in these listed 1933 Nash sizes, so the practical limit should be set by overall condition, inflation, and the car's broader mechanical readiness rather than by assuming modern cruising behavior.

On a 1933 Nash, the vehicle's own age, suspension condition, braking ability, and steering health are just as important as the tires once road speed rises. A well-sorted car on fresh bias-ply tires can be enjoyable on secondary roads and moderate highway use, but long high-speed running is a different proposition than in a later car. Treat the tire as one part of a complete roadworthiness picture, not the only factor.

Published pressure figures for some 1933 Nash tires appear with the listed products, and they vary by size. In 550-18, examples include 1000 pounds at 32 psi and 1125 pounds at 32 psi depending on product. In 700-18, listed products show 1520 pounds at 36 psi. Those figures are tire ratings, not a blanket recommendation to use one pressure across every 1933 Nash model or every tire size.

The best practice is to start with the factory guidance for your specific 1933 Nash model, then compare it with the tire maker's rating information for the exact reproduction tire you are using. Do not transfer a 700-18 pressure assumption to a 550-18, and do not assume all products in the same family are identical. Matching pressure to the correct size and vehicle helps preserve both handling character and tire life.

Before a longer drive in a 1933 Nash, inspect all tires for cracking, cuts, bulges, irregular wear, and stable air pressure, and do not forget the spare. Look closely at the sidewalls, since age tends to show there first on prewar bias-ply tires. If the car has been sitting, check for flat-spot feel during the first few miles and reassess if the vibration does not settle out. A longer drive also calls for a basic once-over of brakes, steering, wheel bearings, and fluid levels.

That preparation matters more on a 1933 Nash than on a modern daily driver because the car's safety margin depends on the whole package working together. Tires that seem acceptable around town may reveal age or inflation issues once heat and distance build. A few minutes spent checking the car before departure can prevent a roadside problem and make the trip far more relaxed and enjoyable.