The 1978 Dodge Charger came from an era when the nameplate had shifted away from its earlier muscle-car identity and into a personal-luxury coupe role, where style, stance, and road manners mattered as much as outright performance. That makes tire fitment especially important, because the look of the car and the way it sits on the road are closely tied to the correct size. This Charger uses 15-inch vintage alphanumeric radial sizes, with FR78-15, GR78-15, or HR78-15 depending on the engine-equipped Special model. The real choice is confirming the exact sub-model first, then selecting the right radial profile for the car's appearance and wheel setup.
Which Tire Size Is Right for The 1978 Dodge Charger
Three primary tire sizes apply to the 1978 Dodge Charger, and the correct one depends on the exact Special sub-model and engine combination. All three are vintage alphanumeric radial sizes built for 15-inch rims, so the first step is identifying whether your Charger uses FR78-15, GR78-15, or HR78-15 before comparing tire choices or evaluating how the car currently sits.
FR78-15 is a vintage alphanumeric radial size in which the letter designation identifies the tire's relative size class, the R confirms radial construction, the 78 refers to the profile family, and 15 designates the rim diameter in inches. On a 1978 Dodge Charger, this size belongs to certain Charger Special configurations rather than every version of the car. Its radial construction suits the late-1970s fitment context of this model. FR78-15 is the size to evaluate when your Charger carries that specific setup and you want to preserve the car's intended scale on a 15-inch wheel.
Fit(s): Special w/318 & 360 Eng. and Special w/400 Eng.
Construction: Radial|Rim: 15 in
GR78-15 follows the same vintage alphanumeric radial sizing system, with the letter marking the size class, the R indicating radial construction, the 78 showing the profile family, and the 15 identifying the wheel diameter. This size appears across more than one 1978 Dodge Charger Special engine combination, making it a key fitment to confirm before moving forward. Because it sits in the middle of the Charger size range here, it is especially important to match it to the actual sub-model and existing wheel setup. That helps maintain proper overall presence and avoids choosing a size meant for a different configuration.
HR78-15 is another vintage alphanumeric radial size, with the letter denoting a larger size class than FR78-15 or GR78-15, the R confirming radial construction, and the 15 indicating a 15-inch rim. On the 1978 Dodge Charger, it applies to the Charger Special with the 400 engine rather than across the full model range. This makes it a fitment-specific choice, not simply an upgrade from the other sizes. HR78-15 is the size to consider when the car's original wheel-and-tire combination or current verified setup calls for that larger radial specification.
Sub-model fitment matters on the 1978 Dodge Charger because tire size changes with the Special model's engine configuration. Since all of these fitments use 15-inch radial tires, the key is confirming which Special version you have before selecting between the applicable alphanumeric sizes.
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1978 Dodge Charger Special w/318 & 360 Eng.
The 1978 Dodge Charger Special with 318 and 360 engines uses FR78-15 or GR78-15 radial sizing, so tire selection starts with confirming which of those two sizes matches the car's actual wheel-and-tire setup. That keeps the choice focused on the correct radial fitment instead of moving into a larger size intended for a different engine configuration.
The 1978 Dodge Charger Special with the 400 engine uses GR78-15 or HR78-15 radial sizing, placing it in the larger end of the Charger fitment range for this year. That makes wheel-and-size verification especially worthwhile before replacing tires, particularly if the car has been changed from its earlier tire setup.
The tire sizes listed on this page assume factory-standard vehicle configuration. The following modifications may affect tire fitment and are not reflected in this guide:
Suspension changes (lowering, lift kits, spring replacements)
Body alterations (fender modifications, custom bodywork)
If your vehicle has been modified from factory specifications, verify tire clearance before purchase.
Frequently Asked Questions
Tire questions for a 1978 Dodge Charger usually come down to identifying the right alphanumeric radial size for the exact Special model, understanding what FR78-15, GR78-15, or HR78-15 means, and checking wheel fitment before putting the car back on the road.
Tire Size & Fitment
What tire size fits a 1978 Dodge Charger?
A 1978 Dodge Charger uses one of three primary tire sizes: FR78-15, GR78-15, or HR78-15. All three are vintage alphanumeric radial sizes for 15-inch rims, and the correct fitment depends on the exact Charger Special sub-model and engine combination rather than applying universally across every car wearing the Charger name for that year.
The practical next step is matching the tire size to the actual car before ordering replacements. A Charger Special with 318 and 360 engines uses FR78-15 or GR78-15, while the Charger Special with the 400 engine uses GR78-15 or HR78-15. Checking the wheel diameter and the size already fitted to the car helps prevent choosing a size intended for a different configuration.
What size rim does a 1978 Dodge Charger use?
The tire fitments covered for the 1978 Dodge Charger use a 15-inch rim. That applies to FR78-15, GR78-15, and HR78-15, all of which share the same rim diameter even though the size designation changes by sub-model and engine combination.
Rim diameter is only one part of the fitment picture, so it should be confirmed alongside the actual tire size the car needs. A 15-inch wheel can still be paired with different alphanumeric radial sizes, and those sizes were not assigned to every Charger the same way. Looking at the existing wheel and verifying the exact Special model keeps the replacement choice on the right track.
Do all 1978 Dodge Charger sub-models use the same tire size?
No, the 1978 Dodge Charger sub-models do not all use the same tire size. The Charger Special with 318 and 360 engines uses FR78-15 or GR78-15, while the Charger Special with the 400 engine uses GR78-15 or HR78-15, so there is overlap but not a single shared size across every covered configuration.
That variation means the sub-model matters just as much as the year, make, and model name. GR78-15 appears in both engine groups, but FR78-15 and HR78-15 do not. A quick check of the engine-equipped Special model, the wheel size, and the current tire markings helps narrow the choice and avoids selecting a tire meant for a different Charger setup.
Choosing the Right Tire
What should I consider when choosing a FR78-15, GR78-15, or HR78-15 tire for a 1978 Dodge Charger?
Start with the exact tire size your 1978 Dodge Charger requires, because FR78-15, GR78-15, and HR78-15 are not interchangeable descriptions of the same fitment. Each is a vintage alphanumeric radial size for a 15-inch rim, but the proper choice depends on the Charger Special engine configuration and the wheel-and-tire setup actually on the car.
Once the size is confirmed, compare the tire's overall role in the car's presentation and use. A replacement should suit the way the Charger sits, the wheel diameter already in service, and the clearance available around the fenders and steering components. If the car has been changed over the years, it is worth verifying the current wheels before assuming the existing tire size is still correct.
How do I choose between the available 1978 Dodge Charger tire sizes?
Choosing between the available 1978 Dodge Charger tire sizes is mainly a fitment question, not a style preference. FR78-15, GR78-15, and HR78-15 each belong to specific Charger Special configurations, so the right choice comes from matching the tire to the sub-model and existing 15-inch wheel setup rather than selecting by appearance alone.
The most useful check is to confirm the exact Special model and compare that with the size currently mounted on the car. GR78-15 overlaps between both engine groupings, while FR78-15 and HR78-15 are more specific. That makes it wise to inspect the wheel, read the sidewall markings, and look for any signs that the car may have been fitted with a different wheel-and-tire package over time.
What tire size should I use for my 1978 Dodge Charger sub-model?
The 1978 Dodge Charger Special with 318 and 360 engines uses FR78-15 or GR78-15, while the 1978 Dodge Charger Special with the 400 engine uses GR78-15 or HR78-15. All of these are radial tires for 15-inch rims, but the exact size should match the sub-model and the car's verified wheel-and-tire setup.
That means the safest path is to identify the sub-model first, then confirm the wheel diameter and the tire markings already on the car. Because GR78-15 appears in both configurations, the presence of a 15-inch wheel alone does not settle the question. Matching the size to the specific Charger Special setup helps preserve proper fitment and keeps the tire choice tied to the way the car was configured.
Restoration & Appearance
Which tire should I choose for a period-style 1978 Dodge Charger?
A period-style 1978 Dodge Charger restoration starts with the correct primary size for the exact Special model: FR78-15, GR78-15, or HR78-15. Because this car uses vintage alphanumeric radial sizing on 15-inch rims, keeping that same sizing format is an important part of maintaining the right late-1970s visual character.
Appearance and fitment work together on a restoration-minded Charger, so the tire should suit the car's stance as well as its sub-model. The best approach is to confirm the specific engine-equipped Special model and then choose the matching radial size. If exact originality matters beyond basic fitment, marque references and vehicle-specific historical documentation are worth checking before finalizing the tire choice.
Does correct tire fitment matter for a 1978 Dodge Charger restoration?
Yes, correct tire fitment matters on a 1978 Dodge Charger restoration because the tire size strongly affects the car's profile, ride height impression, and overall late-1970s presentation. Using the proper FR78-15, GR78-15, or HR78-15 size for the right Special model keeps the car visually consistent with its intended wheel-and-tire scale.
Fitment also affects practicality, since a tire chosen for a different Charger configuration may not suit the car's current wheel setup or body clearance the same way. Even when the rim diameter stays at 15 inches, the alphanumeric size still needs to match the sub-model. A restoration-oriented replacement works best when the tire size is verified before appearance preferences guide the final selection.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1978 Dodge Charger?
Yes, modifications can affect tire fitment on a 1978 Dodge Charger even when the car still uses a 15-inch wheel. Changes such as aftermarket wheels, altered wheel width, suspension work, lowering, or body changes can influence whether an FR78-15, GR78-15, or HR78-15 tire still suits the car's available space and overall setup.
That is why a modified Charger should be measured rather than assumed to follow stock-type fitment. Steering clearance, fender clearance, and the actual wheel dimensions matter as much as the sidewall size marking. A quick inspection before replacement can prevent choosing a tire that matches the sub-model on paper but does not suit the way the car is currently built.
What should I inspect before driving a 1978 Dodge Charger on new tires?
Before driving a 1978 Dodge Charger on new tires, inspect the wheels for the correct 15-inch diameter, confirm the tires match the car's proper FR78-15, GR78-15, or HR78-15 fitment, and look over the suspension and steering for anything that could affect clearance. Tire pressure and visible installation issues should also be checked before regular road use.
A collector-era car often needs more than a simple tire change, especially if it has spent long periods parked. It helps to watch for rubbing at full steering lock, air loss after mounting, and any uneven stance that could point to suspension issues. A short local drive followed by another visual check is a sensible way to confirm the setup is behaving properly.
How should FR78-15, GR78-15, or HR78-15 tires on a collector 1978 Dodge Charger be maintained?
Collector-car tires on a 1978 Dodge Charger should be kept properly inflated, inspected regularly for cracking, bulges, cuts, and uneven wear, and checked for air loss even when the car is driven only occasionally. FR78-15, GR78-15, and HR78-15 tires may spend long periods parked, so condition matters just as much as tread depth.
Storage habits make a real difference on a low-use Charger. Keeping the car away from prolonged heat, direct sunlight, excess moisture, and ozone-producing equipment can help preserve the tires between drives. It is also smart to inspect them before any longer outing, since an older collector vehicle can develop tire-related issues quietly while sitting still.
