1964 Jaguar 2.4, 3.4, 3.8 & 3.8S Tires

The 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S uses two primary tire sizes: 185R15 in radial construction and 640-15 in bias-ply construction. Both are 15-inch fitments, so the choice is not about changing rim diameter but about matching the car’s actual wheel and tire setup.

That matters because a car set up for radial tires may not be wearing the same wheel width or have the same appearance goals as one kept on bias-ply tires. Checking the size stamped on the current tires, measuring wheel width, and looking for prior wheel changes will usually answer which path makes the most sense before replacement.

The primary tire fitments for the 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S are built around a 15-inch rim diameter. Both the 185R15 radial and the 640-15 bias-ply share that same 15-inch wheel diameter, which keeps rim diameter simple even though construction type varies.

Rim diameter is only one part of the fitment picture, though. Wheel width still needs to suit the tire being considered, especially when moving between a narrow bias-ply fitment and a radial alternative. A quick check of the wheel itself can prevent choosing a tire that matches the diameter but not the wheel’s usable width range.

640-15 is a vintage numeric bias-ply size. The 640 portion refers to a nominal section width of about 6.40 inches, while the 15 indicates the rim diameter in inches. On a 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S, it represents the bias-ply fitment rather than the radial 185R15 option.

Understanding that format helps when comparing old and modern sizing systems. A numeric bias-ply code does not read the same way as a metric radial size, so the buyer should not compare the numbers at a glance and assume they mean the same thing. Wheel width, construction type, and intended appearance all deserve attention before making a change.

640-15 is a bias-ply tire size for the 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S. It is the traditional numeric fitment in this application, while 185R15 represents the radial-format primary fitment. The two sizes share a 15-inch rim diameter, but they are different sizing systems and different constructions.

That distinction affects both selection and appearance. A buyer staying with 640-15 can focus on classic bias-ply brands and sidewall treatments, while a buyer considering a radial path should compare actual radial-equivalent sizes and wheel compatibility rather than assuming any 15-inch radial will serve the same role. Construction choice should match the car’s current setup and driving priorities.

Radial equivalents for 640-15 include 175R15 as an 80-series metric radial, P175/75R15 as a P-metric 75-series radial, and P185/70R15 as a P-metric 70-series radial. A recommended rim-width range of 5 to 6 inches is associated with those radial equivalents.

Those options give the buyer several ways to move from a numeric bias-ply size into modern radial sizing, but they should still be treated as alternatives rather than automatic replacements. The next checks are wheel width, overall tire dimensions, steering clearance, and fender clearance. Cars with changed wheels or suspension deserve especially careful measurement before conversion.

Either can be appropriate, because this Jaguar has both a bias-ply primary fitment in 640-15 and a radial primary fitment in 185R15. The better choice depends on whether the car is being kept in a more traditional period-style presentation or set up for radial use with a more modern construction.

Bias-ply tires preserve an earlier visual character, especially when paired with blackwall or whitewall styles in the proper size family. Radials open the door to Euro-metric touring choices and redline options, but they should be matched to suitable wheel width and checked for clearance. A car that has already been converted should be evaluated as it sits rather than by assumption.

Start with the basics: confirm whether the car is using 185R15 radial tires or 640-15 bias-ply tires, and confirm that the wheels are 15-inch rims suited to that tire choice. Construction is the first major decision, because it shapes the size family, appearance, and the kinds of products that make sense.

After that, compare sidewall style, brand, tire series, and wheel-width compatibility. Some owners want blackwall simplicity, while others prefer narrow whitewall, wide whitewall, or redline presentation. It also helps to think about how the car is used, whether for preservation, touring, or occasional local driving, so the tire complements both the Jaguar’s look and its real road use.

Sidewall choices for this Jaguar include blackwall, narrow whitewall, wide whitewall, and redline, depending on the tire size and series selected. The 185R15 radial options include blackwall, narrow whitewall, and redline treatments, while the 640-15 bias-ply range adds both blackwall and whitewall styles in several widths.

That variety lets the tire do more than simply fit the rim. Sidewall treatment has a strong effect on the car’s visual balance, especially on a 1960s Jaguar sedan with clean, formal body lines. The right choice comes down to whether the goal is understated touring style, a brighter restoration-oriented look, or a more sporting presentation with redline detail.

Tires for the 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S are available from Coker Classic, Michelin, Avon, Universal Vintage Tire, BFGoodrich, Firestone, and Excelsior. Those brands cover both 185R15 radial and 640-15 bias-ply fitments, so the brand choice usually follows the size and construction choice rather than replacing it.

A useful way to compare them is by tire series, sidewall style, and wheel-width compatibility instead of by name alone. Michelin and Avon appear within the radial and specialty touring side of the range, while BFGoodrich, Firestone, and Excelsior cover traditional bias-ply choices. Matching the brand to the tire format you actually need keeps the selection process much clearer.

A period-style starting point for a 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S is usually the 640-15 bias-ply fitment, especially when the goal is to preserve an earlier visual character. That size is available in blackwall, narrow whitewall, and wide whitewall variations, which gives some flexibility without leaving the traditional size family.

The final choice should still reflect the car’s present wheel setup and the level of historical accuracy being pursued. Some restorations favor a very specific visual treatment, and exact originality can depend on market, delivery details, and vehicle history. When that level of precision matters, marque references and period documentation are worth checking before settling on sidewall style.

Tire construction changes more than road feel on a restored 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S; it also changes the visual impression of the car. A 640-15 bias-ply tends to support a more traditional presentation, while a 185R15 radial introduces a later-style metric tire format, even when offered with vintage-friendly sidewall treatments.

That is why appearance-minded buyers should decide early whether the restoration leans toward period style or toward regular road use with a classic look. Redlines, blackwalls, and whitewalls each shift the car’s character in a different direction. Looking at wheel width, ride height, and the overall stance of the finished car helps the tire choice feel intentional rather than incidental.

Yes. A 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S may have aftermarket wheels, altered ride height, suspension work, or brake changes that affect tire fitment even when the car still uses a 15-inch rim. Those changes can influence usable wheel width, tire clearance, and whether a bias-ply or radial setup remains appropriate.

That makes a physical inspection more useful than relying on age alone. Looking at the wheel width, checking tire-to-fender and tire-to-suspension clearance, and confirming that the current size matches the wheel can prevent expensive mistakes. Any car that has changed hands several times deserves that extra verification before a replacement set is chosen.

Before road use, inspect tire pressure, valve stems, tread condition, sidewalls, and wheel hardware on the 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S. Even with new tires installed, the car still needs sound wheels, proper balance, and enough clearance at full steering lock and through normal suspension movement.

A collector car also benefits from a wider walk-around before the first drive. Check for rubbing marks inside the wheelhouse, verify that aging suspension bushings are not letting the tire move into contact points, and watch for air loss after installation. A short local drive followed by a second inspection is a smart way to confirm everything has settled correctly.

Collector-car tires on a 1964 Jaguar 2.4, 3.4, 3.8 & 3.8S should be kept clean, properly inflated, and inspected regularly for cracking, flat spotting, bulges, cuts, and uneven wear. Low annual mileage does not stop rubber from aging, so condition matters just as much as tread depth on a car that spends long periods parked.

Storage conditions matter too. Keeping the car away from prolonged sunlight, excess heat, moisture, and ozone-producing equipment helps protect both bias-ply and radial tires. Moving the vehicle occasionally, checking pressure before each outing, and re-inspecting the sidewalls after storage can catch problems early and make the car more enjoyable once it is back on the road.