640-13 Tire Size Guide

The 640-13 uses a vintage numeric size format. In this code, 6.40 is the nominal section width in inches and 13 is the wheel diameter in inches, so the tire is built for a 13-inch rim and carries a nominal width of 6.4 inches.

Unlike a modern P-metric size, the 640-13 does not directly include an aspect ratio or a radial construction letter in the code itself. Buyers looking at this size are usually dealing with a period-style fitment, so the actual tire construction, sidewall styling, load rating, and wheel compatibility need to be confirmed from the tire being chosen rather than assumed from the size code alone.

The 640-13 fits a 13-inch wheel, which equals 330.2 millimeters in diameter. Wheel diameter must match exactly, because a tire built for a 13-inch rim cannot be safely mounted on any other rim diameter.

Wheel width matters too, not just wheel diameter. In this size, the tire is intended for rims from 4.00 to 4.50 inches wide, and using a wheel outside that span can change the tire's profile and how it sits in the wheel opening. A wheel that is too narrow pinches the casing, while an overly wide wheel stretches it flatter than intended.

The 640-13 has a nominal section width of 6.4 inches, which is about 162.6 millimeters. Section width is the overall width of the inflated tire from sidewall to sidewall, not the width of the tread that actually contacts the road.

Clearance checks should be based on section width because the sidewall bulge is usually what comes closest to fenders, steering arms, and suspension parts. Tread width is normally narrower, so using tread alone can understate how much room the tire really needs. On older cars with tight wheel houses, that distinction matters when preserving both appearance and safe turning clearance.

Yes, 640-13 and 6.40-13 refer to the same basic vintage size. The difference is simply how the code is written, with some listings using a decimal point and others dropping it for a shorter numeric style.

Other written forms such as 64013, 640 13, 640X13, and 6.40X13 are also common search variations. Even so, buyers should still read the full sidewall details because the same basic size can appear with different construction, load ratings, speed markings, or sidewall styles. Matching the notation is only the first step; matching the tire's actual specifications is what matters for fitment.

The 640-13 is commonly a tube-type fitment and is often set up with a tube. Even so, tube use is a wheel-and-tire-system question rather than a size question, so the final decision should be confirmed against the actual tire and wheel being used.

Older wheels, especially those from the original bias-ply era, may have rim designs or condition issues that influence whether a tube is appropriate. The safest approach is to inspect the wheel, confirm how the tire is built, and follow the guidance that applies to that exact combination. This matters most on collector cars that may still wear original-style wheels or have wheels that were restored years ago.

A 640-13 in the available product range weighs 19 pounds. Tire weight is measured without the wheel, so it reflects the tire alone rather than the complete mounted assembly.

Weight affects more than shipping or handling. It contributes to unsprung weight, which can influence how an older suspension reacts over bumps and how the steering feels at low speed. On a small vintage passenger car, even a modest difference in tire construction can change the overall feel, so buyers restoring a car to original-type behavior often pay attention to more than just the size stamped on the sidewall.

The 640-13 is associated with classic passenger cars from the 1950s into the late 1960s. It appeared on a range of smaller and mid-size cars, so it belongs to the postwar passenger-car market rather than truck, muscle-car, or off-road applications.

Fitment still depends on the complete wheel and tire package, not just a size match. Buyers should compare the actual wheel diameter, wheel width, suspension clearance, and the vehicle's load needs before settling on this size. On restoration projects, factory service literature and original wheel specifications remain the best reference for confirming whether 640-13 is the right choice for the specific car.

No. The 640-13 requires a 13-inch rim diameter, but wheel width and overall wheel design also matter. In this size, the intended rim width range is 4.00 to 4.50 inches, so not every 13-inch wheel will place the tire in its proper shape.

A wider or narrower wheel can change sidewall profile, section width, and the way the tire sits under the car. Older cars can also vary in backspacing, brake clearance, and steering clearance even when the wheel diameter is correct. Buyers should treat the 13-inch diameter as only one part of the fitment picture and verify the full wheel dimensions before mounting.

The 640-13 is often a strong choice when a restoration calls for authentic postwar passenger-car proportions and bias-ply construction. Its tall, narrow shape and bias-ply build align with the type of tire many cars of the 1950s and early 1960s originally used.

Originality-minded owners should still compare sidewall style, load rating, and wheel width along with the size itself. A car judged closely on appearance may need more than just the right numeric code to look correct. Matching the construction style, the tire's visual profile, and the way it fills the wheel opening is usually what separates a merely usable replacement from a truly convincing restoration fitment.

A 640-13 bias-ply tire generally delivers the road feel expected from a vintage passenger car, with a tall sidewall and more traditional carcass flex than a modern radial. Many owners choose it because it preserves the steering character and overall personality that older suspensions were designed around.

Ride and handling are influenced by more than construction alone. Suspension wear, alignment, wheel condition, vehicle weight, and tire age all affect how the car tracks and responds. On a well-sorted classic, this size can keep the vehicle's original character intact, but drivers used to modern radial behavior should expect a different feel in steering response and road feedback.

A radial substitute for the 640-13 may change steering response, ride character, and the tire's overall visual profile. The commonly compared options include 175R13, P175/75R13, P185/70R13, and 650R13, and each can alter the balance between original appearance and modern-road manners.

Differences in diameter and section width can affect wheel-opening fill, stance, and speedometer behavior, while construction changes can influence how the car reacts in turns and over pavement seams. Buyers comparing a radial replacement should look beyond the label and measure the installed dimensions carefully. A substitute that works physically may still change the character of the vehicle more than a restoration-minded owner wants.

The 640-13 can be used on today's roads when the tire is in proper condition and matched to the vehicle's wheel and load requirements, but buyers should approach it as a vintage-style size rather than assume modern driving behavior. Bias-ply construction brings a different feel than later radial designs.

Before extended use, inspect the tire's age, condition, and inflation, and make sure the suspension and alignment are in sound order. Road manners on an older car are shaped by the whole system, not the tire alone. Drivers planning frequent higher-speed use often compare equivalent radial sizes as well, while owners focused on originality usually accept the more traditional response that comes with a bias-ply setup.

BFGoodrich is available in the 640-13 size. In this case, the size is represented by a classic bias-ply offering rather than a broad multi-brand field, so buyers should pay close attention to the tire's construction, appearance, and load details.

When only a limited number of options exist in a vintage size, the decision usually comes down to how closely the tire matches the vehicle's intended use. Some owners are chasing factory-style appearance, while others mainly want dependable replacement rubber for occasional road use. Checking the sidewall treatment, the wheel width range, and the load rating is more useful than focusing on brand name alone.

A quality 640-13 should match the vehicle's intended use in three basic ways: correct construction, correct dimensions, and correct load capacity. For a vintage passenger car, that means the tire should fit the proper 13-inch rim, sit correctly on a 4.00 to 4.50 inch wheel, and carry the load the vehicle actually places on it.

Appearance matters too in a size from the bias-ply era. A tire that has the right numeric code but the wrong sidewall look or overall profile can make a restored car appear slightly off even when it mounts correctly. Buyers usually get the best result by selecting a full matched set so the car keeps consistent stance, sidewall presentation, and handling characteristics from corner to corner.

Yes, sidewall style can matter a great deal in the 640-13 because the available tire in this size uses a wide whitewall design. On many 1950s and early 1960s passenger cars, the sidewall treatment is a major part of the vehicle's finished look, not just a cosmetic extra.

Owners restoring a car to a factory-style presentation often judge the sidewall by proportion as much as by color. A wide whitewall can strongly influence how formal or upscale the car appears once mounted. Buyers should think about how the tire will look with the car's trim, wheel covers, and ride height so the overall presentation stays consistent with the era they are trying to capture.

The 640-13 should be stored the same way any vintage-style tire should be stored: away from prolonged sunlight, excess heat, moisture, and ozone sources such as electric motors or battery chargers. Clean, dry storage conditions help protect the casing and sidewall from premature aging while the vehicle is parked.

Collector cars that sit for long periods deserve occasional inspection even when they are not being driven much. Look for cracking, flat spotting, air loss, bulges, or sidewall distress before putting the car back on the road. Bias-ply tires can age out long before the tread is worn, so low mileage does not remove the need for routine condition checks.

The 640-13 should be inspected regularly for cracks, cuts, bulges, uneven wear, and loss of air pressure, especially before longer drives. A vintage-size bias-ply tire may spend long periods parked, which makes condition checks just as important as tread depth.

Inspection should also include the wheels and valve hardware, particularly if the setup uses tubes. A tire can look usable at a glance and still have age-related issues that affect reliability on the road. Owners who drive only seasonally should inspect before each outing, while cars driven more often still benefit from a close look at the beginning of every driving month.

The 640-13 is commonly a tube-type fitment, but the final answer comes from the complete wheel-and-tire combination rather than the size code by itself. Buyers should confirm tube use from the actual tire construction, the wheel design, and the guidance that applies to that specific setup.

Older 13-inch wheels can vary in condition and original design, and those differences may affect whether a tube is appropriate. If the vehicle has restored original wheels, aftermarket wheels, or rims of uncertain age, it is wise to inspect them carefully before mounting tires. A qualified tire professional can help determine whether the wheel and tire system should be run with a tube.

The 640-13 should be replaced when age or condition shows up as cracking, bulges, repeated air loss, impact damage, or other visible deterioration, even if plenty of tread remains. Vintage-use tires often age from time, storage, and environment before they wear out from mileage.

Before road use, especially after a long storage period, inspect the full tire and wheel assembly carefully. Sidewall condition, bead area condition, and tube-related issues all matter on older-style fitments. If there is any doubt about the tire's age or structural condition, a cautious inspection by a qualified tire professional is a sound step before putting the car back into service.

In the available 640-13 offering, the tire is rated at 1,045 pounds at 32 psi. That figure is the per-tire load capacity, so it should be considered as part of the vehicle's total weight distribution rather than as a whole-car number.

Buyers should compare that rating to the actual demands placed on the tires when the car is occupied and carrying fuel or luggage. A size match alone is not enough if the load requirement is wrong for the application. On older passenger cars, checking axle weight expectations and using a matched set with the same rating is an important part of responsible fitment.

The most important checks before driving on the 640-13 are tire condition, correct wheel diameter, proper wheel width, inflation condition, and overall clearance. In this size, the tire is built for a 13-inch wheel and fits rims from 4.00 to 4.50 inches wide, so wheel compatibility should be confirmed before any road use.

Longer trips deserve extra attention because heat, speed, and load can expose problems that may not show up around town. Inspect for cracking, cuts, bulges, and signs of rubbing, and make sure the wheels are in sound condition if tubes are part of the setup. Buyers should also review current sidewall markings and confirm that the tire suits the way the vehicle will actually be driven.