1978 Jeep CJ5 & CJ7 Tires

The 1978 Jeep CJ5 & CJ7 uses three primary 15-inch tire sizes: F78-15, H78-15, and HR78-15. F78-15 and H78-15 are vintage alphanumeric bias-ply sizes, while HR78-15 is an alphanumeric radial size. That means the correct answer depends on the Jeep’s actual wheel-and-tire setup rather than assuming every example uses the same construction.

A close check of the tires already on the Jeep is the best starting point, followed by confirming the wheel diameter is still 15 inches. If the Jeep has been modified over the years with different wheels, suspension changes, or a different tire type, matching the replacement to the current setup is more important than guessing from appearance alone.

The covered tire fitments for a 1978 Jeep CJ5 & CJ7 all use a 15-inch rim diameter. That includes F78-15, H78-15, and HR78-15. Even though the size options vary by section and construction, the common fitment point across them is the 15-inch wheel.

Rim diameter should still be confirmed on the Jeep before ordering tires, especially on vehicles that may have seen decades of service, replacement wheels, or aftermarket upgrades. Diameter alone is not the whole fitment story, so wheel width and clearance also matter when moving between different size families or considering a radial-equivalent alternative.

F78-15 is a vintage alphanumeric bias-ply size. The F indicates the tire’s size class, the 78 marks its profile family, and the 15 identifies the rim diameter in inches. On a 1978 Jeep CJ5 & CJ7, it represents a traditional period-style tire format rather than a modern metric or P-metric sizing system.

That older sizing style matters because replacement choices may include both bias-ply tires and radial equivalents that use very different-looking size codes. Staying with F78-15 keeps the Jeep in its original fitment family, while moving to an equivalent should prompt a check of wheel width, overall tire dimensions, and clearance around the suspension and body.

F78-15 is a bias-ply tire size for the 1978 Jeep CJ5 & CJ7. It uses the vintage alphanumeric bias-ply format rather than a radial construction code. Within this fitment family, HR78-15 is the radial-format primary size, while F78-15 remains the traditional bias-ply choice.

That distinction affects both appearance and replacement planning. A buyer trying to preserve a period-style Jeep may prefer to stay with bias-ply construction, while someone evaluating a different driving feel may look at radial alternatives instead. Before changing construction, it is smart to confirm wheel width, current clearance, and whether the Jeep’s suspension and steering setup are still close to stock.

Radial equivalents for F78-15 include 195R15 as an 80-series metric radial, P205/75R15 as a 75-series P-metric radial, P215/70R15 as a 70-series P-metric radial, and 670R15 as a bias-look radial. Those options give the 1978 Jeep CJ5 & CJ7 several different radial-sizing paths while staying within the 15-inch rim family.

The practical difference is that these choices use different sizing conventions and may suit different goals. A bias-look radial is often attractive when traditional presentation matters, while metric and P-metric options speak a more modern sizing language. The recommended rim-width range for this equivalent group is 5 to 7 inches, and dimensions and clearance should be checked before making a conversion.

A 1978 Jeep CJ5 & CJ7 can legitimately lead to either choice, because the covered fitments include both bias-ply sizes and a radial-format size. Bias-ply options keep the Jeep in a more traditional tire family, while radial choices open the door to a different construction approach. The better direction depends on how the Jeep is meant to look and be used.

Owners focused on restoration-minded appearance often begin with the original-style bias-ply fitment family, while a driver-oriented approach may encourage a closer look at radial sizing. Either way, the safest path is to verify the actual wheel setup first. Construction changes should be treated as a fitment decision, not just a size decision, because wheel width and vehicle clearance still matter.

Start with the Jeep’s actual primary size and construction: F78-15 and H78-15 are bias-ply choices, while HR78-15 is a radial-format fitment, all on 15-inch rims. From there, the selection process becomes more specific. Sidewall style, tire series, and whether the Jeep is meant to present as a restoration-oriented vehicle or a more utilitarian truck all begin to matter.

Wheel width should be checked before narrowing the field, especially on vehicles that may no longer wear their original wheels. Intended use matters too, because a wide whitewall bias-ply tire gives the Jeep a very different visual impression than a blackwall truck-style tire. Choosing carefully helps the tire match both the vehicle’s stance and the owner’s expectations.

Available H78-15 products for the 1978 Jeep CJ5 & CJ7 include both wide whitewall and blackwall sidewall styles. That gives this fitment two very different visual directions. A wide whitewall presents a more restoration-oriented appearance, while a blackwall treatment leans toward a plainer, more functional truck-style look.

Sidewall style should be chosen with the Jeep’s overall character in mind rather than as an afterthought. A CJ built around a period-style presentation may look more cohesive with whitewalls, while a more utility-focused example may suit blackwalls better. Sidewall treatment does not replace the need to verify size, wheel compatibility, and construction before making the final pick.

H78-15 tires for the 1978 Jeep CJ5 & CJ7 are available from Coker Classic and STA. In this size, Coker Classic appears in wide whitewall form within the Coker Classic Bias Ply series, while STA offers the Traxion line with a blackwall presentation and a more truck-oriented character.

Brand choice works best when it is tied to the kind of Jeep being built or maintained. A buyer comparing these options should look at sidewall style, tire series, load figures, and rim-width compatibility rather than choosing by brand name alone. That approach keeps the focus on matching the tire to the Jeep’s fitment and intended use.

A period-style 1978 Jeep CJ5 & CJ7 usually starts with one of the primary vintage-size fitments, especially F78-15 or H78-15 in bias-ply construction. Those sizes preserve the older alphanumeric tire format that suits the era of the vehicle. Choosing between them still depends on the Jeep’s actual wheel-and-tire setup rather than appearance alone.

After the size is confirmed, the next question is how formal or how utilitarian the Jeep should look. A wide whitewall H78-15 creates a very different presentation from a blackwall truck-style tire in the same size family. For exact originality questions, marque-specific references and restoration documentation remain the best way to confirm what is appropriate.

Tire construction changes more than just driving character on a restored 1978 Jeep CJ5 & CJ7. A bias-ply tire keeps the Jeep in a traditional fitment family that looks visually at home on a late-1970s utility vehicle, while a radial format can introduce a more modern presentation even when the rim diameter stays the same.

That makes construction part of the restoration decision, not just a technical specification. Buyers who want a vintage look often begin with bias-ply sizing or a bias-look radial if one is available for the chosen size. Anyone moving away from the original-style construction should still confirm wheel width and clearance before judging the result on appearance alone.

Yes, modifications can affect tire fitment on a 1978 Jeep CJ5 & CJ7 even when the replacement tire is in a correct 15-inch fitment family. Aftermarket wheels, changed wheel widths, suspension lifts, steering alterations, or body modifications can all influence how an F78-15, H78-15, or HR78-15 tire sits and clears.

That is why the actual Jeep in front of you matters more than assuming every CJ remains stock. A replacement tire should be checked against current wheel diameter, wheel width, and clearance at full steering lock and normal suspension travel. Taking those measurements first helps avoid choosing a tire that is correct on paper but problematic on the vehicle.

Before putting a 1978 Jeep CJ5 & CJ7 back on the road with new tires, inspect the wheels, valve stems, lug hardware, and general suspension and steering condition. The tires themselves should also be checked for proper inflation and for any early signs of rubbing once mounted. A fresh tire cannot compensate for worn or incorrect supporting parts.

A short local drive followed by another visual inspection is a sensible next step. Look for contact marks, uneven seating, air loss, or anything unusual in steering feel. Collector Jeeps often sit for long periods, so it also helps to confirm brakes, alignment condition, and overall road readiness before assuming the new tires are the only part of the equation.

Tires on a collector 1978 Jeep CJ5 & CJ7 should be maintained with regular pressure checks, periodic visual inspections, and attention to age-related condition even if tread wear is minimal. Low-mileage vintage vehicles often spend long stretches parked, which can make cracking, flat spotting, and unnoticed air loss just as important as tread depth.

Good storage habits help as much as routine driving checks. Keeping the Jeep away from prolonged sunlight, moisture, and ozone sources can slow tire aging, and moving the vehicle occasionally can reduce stress from sitting in one position. Before any longer drive, inspect sidewalls, tread surfaces, and clearances so the Jeep is ready for road use rather than simply ready to start.