1938 Pontiac Tire Fitment Guide

1938 Pontiac vehicles use two tire sizes, and the correct one depends on the model. The 1938 Pontiac 6 Cyl. uses 600-16, while the 1938 Pontiac 8 Cyl. uses 650-16. Both sizes are bias-ply tires built for 16-inch rims. Where rim-width guidance is published, 600-16 fits 4.00- to 4.50-inch wheels, while 650-16 fits 4.50- to 5.00-inch wheels.

That split means a 1938 Pontiac owner should confirm the model before choosing a tire, even though both sizes share the same rim diameter. Once the model is identified, the remaining decisions usually come down to sidewall appearance, brand preference, and whether the existing wheel falls within the published rim-width range for that size.

On a 1938 Pontiac, 600-16 is a numeric bias-ply size. The 6.00 portion refers to the nominal section width in inches, and the 16 identifies the wheel diameter in inches. It is not a modern metric size, and it is not an alphanumeric radial code. On 1938 Pontiac applications, 600-16 belongs to the 6-cylinder model.

Understanding that code helps keep a six-cylinder Pontiac owner from confusing it with later sizing systems or with the larger 650-16 used on eight-cylinder cars. It also frames the real shopping decision correctly: first confirm that the car is a 6 Cyl., then choose the preferred sidewall style and brand within the 600-16 size family.

No, 1938 Pontiac models do not all use the same tire size. The 6-cylinder cars use 600-16, while the 8-cylinder cars use 650-16. Both are 16-inch bias-ply sizes, but they are not interchangeable as a year-make-wide fitment choice. The distinction follows the model grouping rather than being shared across the entire Pontiac range.

That matters because a buyer who knows only the year and make is still one step short of the correct tire. On a 1938 Pontiac, confirming whether the car is a six-cylinder or eight-cylinder model is the key step before comparing whitewall versus blackwall styling or choosing among the available manufacturers.

1938 Pontiac tires are available in both blackwall and wide whitewall styles in the two correct size families. The 600-16 options for 1938 Pontiac 6 Cyl. cars include blackwall and wide whitewall products, and the 650-16 options for 1938 Pontiac 8 Cyl. cars do the same. That gives owners room to match the look of a conservative driver, a factory-style restoration, or a more formal prewar presentation.

Sidewall style can change the car's visual character almost as much as the wheel itself on a late-1930s Pontiac. A blackwall usually gives a plainer, more understated appearance, while a wide whitewall leans into the period luxury look that many restorers want. If show authenticity matters, compare your intended style against period photos and the standards used by Pontiac or prewar judging groups.

Several brands produce tires for 1938 Pontiac fitments. In 600-16, the available brands include BFGoodrich, Coker Classic, Firestone, and Avon. In 650-16, the available brands include BFGoodrich, Coker Classic, Firestone, and Garfield. All of the listed 1938 Pontiac fitments remain in bias-ply construction, which suits the period of the car.

Brand choice on a 1938 Pontiac usually comes down to the look you want and the exact product characteristics offered in your model's size. Some owners prioritize a traditional American brand presentation, while others focus on a particular tread or sidewall style. Once the correct size is established, comparing by brand is a sensible final step rather than the first one.

For 1938 Pontiac fitments, BFGoodrich and Firestone both offer period-style bias-ply tires in the correct numeric sizes. In 600-16, both brands publish a 1400-pound maximum load at 32 psi and fit 4.00- to 4.50-inch rims, while BFGoodrich appears in a 3.50-inch whitewall and Firestone in a 3.25-inch whitewall example. In 650-16, both brands publish 1580 pounds at 32 psi with 4.50- to 5.00-inch rim guidance on products where that specification appears.

That means the practical difference for many 1938 Pontiac owners is often presentation rather than a major change in fitment class. Whitewall width, tread styling, and brand appearance on the sidewall can all influence the finished look of the car. For a restoration, those details are often worth comparing just as carefully as the basic size.

Published rim-width guidance for 1938 Pontiac tires depends on the size. The 600-16 size used on 1938 Pontiac 6 Cyl. models fits 4.00- to 4.50-inch rims on products that list that range. The 650-16 size used on 1938 Pontiac 8 Cyl. models fits 4.50- to 5.00-inch rims where that specification is provided. Both sizes use 16-inch wheel diameters.

Rim width matters because two tires can share the same rim diameter and still be intended for different wheel widths. On a 1938 Pontiac, that is exactly why the six-cylinder and eight-cylinder models should not be treated as the same fitment. Measuring the actual wheel before choosing a tire is a smart check, especially on cars that may have had parts swapped over the decades.

Original 1938 Pontiac wheels can match both tire sizes only if the wheel's rim diameter and width correspond to the specific tire being used. Both 600-16 and 650-16 mount on 16-inch rims, so the diameter is shared across the lineup. The important difference is width: 600-16 aligns with 4.00- to 4.50-inch rims where listed, while 650-16 aligns with 4.50- to 5.00-inch rims where listed.

That shared 16-inch diameter can make the two sizes look interchangeable at first glance, but the wheel itself still has to suit the tire. A 1938 Pontiac owner comparing old wheels, spare wheels, or long-ago replacements should confirm the actual rim width before assuming a wheel from one model is appropriate for the other model's size.

A stored 1938 Pontiac should be kept away from direct sunlight, electric motors, battery chargers, welders, and other ozone-producing equipment that can age rubber prematurely. The car should sit in a dry, stable environment, and the tires should be kept at the correct pressure while the vehicle is moved periodically or supported in a way that reduces long static loading. Bias-ply tires are more prone to temporary flat-spotting during storage than modern radial designs.

That matters on a collector car because long parked periods are often harder on the tires than careful road use. If a 1938 Pontiac will sit through a season, even basic steps like cleaning the tires, checking pressure, and rolling the car occasionally can help preserve ride quality and sidewall condition when it is time to drive again.

On a 1938 Pontiac, tire life is usually judged more by age and condition than by accumulated mileage. A collector-car tire should be evaluated regularly once it reaches the five- to seven-year range, and many owners begin seriously considering replacement at around ten years regardless of tread depth. The DOT date code on the tire remains the key way to establish age, even when the car has seen light use.

A prewar Pontiac can spend much of its life parked, trailered, or driven only to events, so tread wear alone is rarely the whole story. Sidewall cracking, hardening, loss of pressure retention, and visible deformation are more meaningful warning signs. When a tire's age and condition begin to raise doubts, replacement is usually wiser than trying to stretch another season out of it.

Tires on a 1938 Pontiac should be checked before every drive and inspected more thoroughly before any longer outing. The routine check should include pressure, visible cracking, tread condition, cuts, bulges, and any sign that the tire is aging unevenly. A car of this era also deserves close attention to the spare, since an old spare is often forgotten until it is needed.

Frequent inspections make sense because collector cars often sit for long periods and then return to road use without much warning. Catching a pressure loss, a damaged sidewall, or a deteriorated valve stem early is far easier than dealing with a roadside failure. A few careful minutes in the garage can prevent problems that spoil a tour or local show drive.

A 1938 Pontiac 6 Cyl. would have been equipped in the bias-ply era, and the correct size family for that model is 600-16. That matches the period construction used across late-1930s American passenger cars and aligns with the size associated with Pontiac six-cylinder models for the year. Original-equipment branding could vary by market and production sourcing, so the key restoration point is the correct size, construction type, and sidewall treatment rather than assuming a single universal brand.

For a careful restoration, that means starting with 600-16 bias-ply tires and then refining the choice around blackwall or wide whitewall presentation. If the car is being judged at a high level, compare your choice with period photographs, Pontiac literature, and advice from marque specialists. Those sources can help sort out market-specific details that go beyond the basic fitment itself.

Correct tire fitment matters quite a bit when showing a 1938 Pontiac, especially in preservation, concours, or marque-focused judging. Size, construction type, and sidewall style all affect whether the car reads as authentically restored. On a late-1930s Pontiac, an incorrect size, a wheel mismatch, or an obviously modern-looking replacement can stand out quickly against otherwise period-correct details.

That does not mean every event uses the same standards, but it does mean tires should be chosen with the car's purpose in mind. A local driver-level show may be forgiving, while a more serious event may scrutinize whitewall width, blackwall use, and whether the car remains in a proper bias-ply format. Event rules and Pontiac club guidance are the best final authority.

For a 1938 Pontiac, the difference between blackwall and wide whitewall tires is primarily visual and historical rather than a change in the underlying fitment class. Both 600-16 and 650-16 are available in blackwall and wide whitewall versions, depending on the brand. Whitewalls tend to emphasize the formal, upscale styling of late-1930s American cars, while blackwalls present a simpler, more restrained look.

That choice can shape the character of the whole restoration. A whitewall can make a 1938 Pontiac appear richer and more period-dressed, especially on a show car, while a blackwall may suit a plainer trim level or an owner who prefers a less ornate appearance. Checking period photos of similar cars is one of the best ways to decide which presentation fits your Pontiac.

1938 Pontiac tires can be suitable for highway driving when they are in good condition, correctly fitted, and used within the capabilities of the tire and the car. The available 600-16 and 650-16 fitments are bias-ply tires, and one 600-size option carries an H speed rating, which corresponds to a 130 mph ceiling. In real use, the mechanical character of a 1938 Pontiac and the behavior of a prewar chassis usually matter more than the tire's theoretical top-speed number.

Highway safety on a 1938 Pontiac is as much about preparation and realistic use as it is about the tire itself. Proper inflation, sound wheels, good steering and suspension condition, and conservative driving expectations all matter. A well-sorted car on fresh, correctly sized tires is far different from an old car running on aged rubber simply because the tread still looks usable.

Inflation pressure on 1938 Pontiac tires should follow the factory vehicle recommendation first, then be checked against the tire maker's published limits for the exact product and size. Several 600-16 products list a maximum load of 1400 pounds at 32 psi, and several 650-16 products list 1580 pounds at 32 psi. Those figures describe a tire's rated load at a stated pressure and should not automatically be treated as the universal running pressure for every Pontiac application.

The practical approach is to use the original owner's or service literature as the starting point for the car, then confirm that the chosen reproduction tire is being used within its published operating range. Pressure should also be checked cold and rechecked regularly, since an older collector car can spend long periods parked between drives.

Before a longer drive in a 1938 Pontiac, inspect each tire for cracking, cuts, bulges, irregular wear, and proper cold inflation pressure. Check the valve stems, confirm the spare is serviceable, and make sure the tire size on the car matches the actual model so that a six-cylinder car is not wearing eight-cylinder fitments or vice versa. On a prewar car, tire condition is only one part of a broader readiness check.

A longer outing is also the right time to think beyond the tires and verify brakes, steering play, wheel fasteners, and fluid levels. Vintage Pontiacs reward a methodical pre-drive routine because small issues become more significant once the car is at road speed and farther from home. Tire inspection is the first step, but it should be part of a complete mechanical once-over.