Mercury Bobcat Tires

Mercury Bobcat uses four sizes across the 1976 through 1980 model run: A78-13, B78-13, BR70-13, and BR78-13. A78-13 appears in 1976, 1978, and 1979; B78-13 appears in 1976 and 1978; BR70-13 appears in 1977, 1979, and 1980; and BR78-13 appears from 1977 through 1980. All of these sizes are built around a 13-inch wheel, but they are not interchangeable simply because the rim diameter matches.

The practical next step is to match the exact year first, then verify the size shown on the car’s current sidewall or original paperwork. A 1978 or 1979 Mercury Bobcat deserves extra care because those years carry three listed sizes, which means the correct tire depends on the specific configuration rather than the year alone.

A78-13 is an older alphanumeric bias-ply size used on certain Mercury Bobcat applications. The letter A identifies a narrow width class, the number 78 is the aspect-series designation, and 13 is the wheel diameter in inches. Because there is no R in the code, A78-13 is a bias-ply size rather than a radial one.

That distinction matters because a Mercury Bobcat fitted with A78-13 is following an earlier tire sizing convention than a Bobcat using BR70-13 or BR78-13. If your car carries A78-13 or B78-13, confirm that the wheel and overall restoration plan are intended for a bias-ply tire rather than assuming any 13-inch radial will serve the same role.

A 1978 Mercury Bobcat can use A78-13, B78-13, or BR78-13, while a 1979 Mercury Bobcat can use A78-13, BR78-13, or BR70-13. Since all of those sizes share the same 13-inch rim diameter, the split is not caused by a wheel diameter change. The multiple listings point instead to configuration differences within the Mercury Bobcat line, such as trim level or body style.

That means the year by itself is not enough to choose a tire for a 1978 or 1979 Mercury Bobcat. Check the original sidewall size if the car still has an old reference tire, compare wheel and suspension setup, and use factory literature or a marque specialist if the car has been restored or modified over time.

Mercury Bobcat sizes A78-13 and B78-13 are bias-ply alphanumeric sizes, and those fitments should be treated as tube-required. BR70-13 and BR78-13 are radial-designated alphanumeric sizes, so they are a different construction type and should not be assumed to follow the same tube requirement. The key point is that tube use on Mercury Bobcat depends on which size family the specific car uses.

If your Mercury Bobcat is running one of the bias-ply sizes, plan around the wheel and tire package as a bias-ply setup rather than piecing it together casually. If it uses one of the radial sizes, verify the wheel condition and intended tire construction before making the final selection so the wheel, tire, and overall fitment approach stay consistent.

Start with the model year, because Mercury Bobcat size usage changes across the short production run. A78-13 appears in 1976, 1978, and 1979; B78-13 in 1976 and 1978; BR70-13 in 1977, 1979, and 1980; and BR78-13 from 1977 through 1980. Since 1978 and 1979 each carry three listed sizes, year alone does not fully settle the question on those cars.

The most reliable approach is to compare the car’s current sidewall marking, wheel diameter, and any surviving factory paperwork or restoration records. That is especially important on a Mercury Bobcat that may have changed from bias-ply sizing to radial sizing at some point in its life, because a later replacement choice can obscure what the car was originally set up to use.

A stored Mercury Bobcat should be kept in a cool, dry, dark space with the tires away from direct sunlight, ozone sources, and prolonged moisture. Clean the tires gently, keep them properly inflated for storage, and avoid leaving the car parked for long periods on contaminated concrete or petroleum-stained surfaces. Long static loading is hard on collector tires even when tread wear is minimal.

If the Mercury Bobcat will sit for months at a time, roll it periodically or support it in a way that reduces flat-spotting and sidewall strain. Owners preserving a more original-style bias-ply setup should be especially attentive, since vintage-format tires tend to react more noticeably to long idle periods than modern daily-driver tires.

Tires on a Mercury Bobcat should be inspected before each drive and more thoroughly at regular intervals even if the car is used only occasionally. Look for cracking, air loss, uneven wear, sidewall bulges, tread separation, and signs that the tire is rubbing because the chosen size does not match the wheel or suspension setup. Collector cars often age their tires out long before they wear them out.

A practical routine is to check inflation and visible condition every time the Mercury Bobcat leaves the garage, then perform a closer inspection several times each season. If the car changes behavior on the road, starts pulling, or develops vibration, treat that as a signal to inspect the tires and wheels immediately rather than simply driving through it.

Mercury Bobcat tires should be replaced when age, cracking, separation, impact damage, or chronic air loss make them questionable, even if the tread still looks usable. Collector-car tires often retain tread because mileage is low, but rubber condition matters more than tread depth on a car that spends much of its life parked. A tire can look respectable in the garage and still be unsuitable for road use.

Use inspection history and age as seriously as appearance when deciding whether a Mercury Bobcat tire remains serviceable. If the car carries an older bias-ply set or an unknown-age period tire, err on the side of caution and have the assembly evaluated before further driving, especially if the car is being returned to regular seasonal use after long storage.

Mercury Bobcat was fitted across its production run with A78-13, B78-13, BR70-13, and BR78-13 depending on year and configuration. The presence of both bias-ply alphanumeric sizes and radial-marked alphanumeric sizes shows that more than one tire approach existed within the Bobcat line. Original fitment for a specific Mercury Bobcat therefore depends on the exact year and version of the car.

For restoration work, use the year listing as the starting point and then verify the individual car through original literature, window sticker records, or marque-club references. That matters most on 1978 and 1979 Mercury Bobcat examples, where several listed sizes can all be correct within the broader model range but not necessarily correct for the same car.

Correct tire fitment can absolutely affect how a Mercury Bobcat is judged and how authentic it appears to knowledgeable buyers. A car wearing the wrong size family, the wrong profile, or a construction type out of character with its original setup can look subtly off even when the wheel diameter is technically correct. On a late-1970s compact, those details often separate a careful restoration from a casual refurbishment.

Judging standards vary, so the smartest course is to match the tire size to the specific year and configuration, then align construction and appearance with the restoration’s purpose. A road-driven Mercury Bobcat may justify different compromises than a show-focused one, but either way, consistency and era-appropriate fitment usually help the car present better and avoid avoidable authenticity questions.

The correct sidewall style for a Mercury Bobcat restoration depends on the exact tire offered in the size you need and the appearance you want the finished car to carry. Late-1970s compact cars could look noticeably different depending on whether the chosen tire leans more economy-oriented, sport-oriented, or simply replacement-oriented in presentation. Sidewall styling should support the era and personality of the individual Mercury Bobcat rather than fight it.

When restoring a Mercury Bobcat, first lock down the proper size and construction family, then compare the sidewall look to period photos, brochures, and survivor cars. That sequence helps avoid choosing a visually appealing tire that is the wrong size family for the car, which is a common mistake when a 13-inch fitment seems simple but actually spans both bias-ply and radial-era choices.

A Mercury Bobcat can be driven on public roads when the tires are the correct size, in sound condition, properly inflated, and matched to a mechanically healthy car. Safety depends on the complete condition of the tire and wheel package, not just whether the sidewall code appears in the correct year range. An aged, cracked, or poorly matched tire is not made roadworthy simply because the size itself is correct.

Road use should begin with an honest inspection of the full car, including tires, wheels, brakes, steering, and suspension. That is especially important on a Mercury Bobcat that may have changed between bias-ply and radial-style fitments over time, because the tire choice should make sense with the car’s current wheel setup and the way it is actually used.

Before driving a Mercury Bobcat, check inflation pressure, visible sidewall and tread condition, valve stems, wheel condition, and signs of rubbing or uneven wear. Make sure the size on the car matches one of the known Mercury Bobcat sizes for the appropriate year and that all four tires follow a consistent fitment approach. Mixed age, mixed condition, or mismatched construction can create problems even at modest speeds.

A short driveway inspection can prevent the most common collector-car tire issues from becoming road issues. If the Mercury Bobcat has been sitting, take extra time to look for flat spotting, cracks around the bead area, and evidence that an older tire is drying out, then ease into use rather than heading straight for sustained highway driving.

A sensible speed for a Mercury Bobcat on original-style tires depends on the tire’s construction, condition, and age rather than the size code alone. A fresh, properly fitted radial-style Mercury Bobcat tire may suit normal collector-car road use differently than an older-style bias-ply setup, especially in steering response and heat tolerance. Condition always matters more than appearance when deciding how far and how fast to drive.

The safe approach is to drive a Mercury Bobcat conservatively until you know exactly what tire type is fitted and how the car behaves on it. If the car is on bias-ply tires, recently revived from storage, or wearing an older set of uncertain age, keep speeds moderate and avoid long high-speed runs until the entire tire and chassis package has proven itself.