1975 Jeep Truck Tire Fitment Guide

The 1975 Jeep Truck uses seven sizes across two models. The J-10 uses H78-15, HR78-15, and 10-15, all on 15-inch wheels. The J-20 uses 800-16.5, 950-16.5, and 875-16.5 on 16.5-inch wheels, plus 750-16 on 16-inch wheels. Rim width guidance is available for H78-15 at 5.50 to 7.00 inches, for 800-16.5 at 6.00 to 6.50 inches, for 950-16.5 at 6.50 to 6.75 inches, and for 750-16 at 5.00 to 6.00 inches.

Model identification matters more on a 1975 Jeep Truck than it does on many year-make pages, because the J-10 and J-20 do not share a common tire family. A 15-inch J-10 fitment is completely different from a 16- or 16.5-inch J-20 fitment, so the best starting point is to verify the truck model and then confirm the actual wheel diameter on the vehicle before choosing a tire.

H78-15 is an alphanumeric bias-ply size used on the 1975 Jeep Truck J-10. In this older sizing system, the H identifies the tire’s section class, the 78 is part of the period alphanumeric designation rather than a modern stand-alone aspect ratio callout, and the 15 means the tire fits a 15-inch wheel. In the products available for this size, H78-15 appears as a bias-ply construction rather than a radial.

That matters because H78-15 belongs to the era when domestic trucks often used alphanumeric sizing instead of today’s metric system. If your J-10 still carries period-style wheels and you want a traditional look, H78-15 is one of the core sizes to compare. It is also offered in more than one sidewall style, so after confirming the size itself, the next decision is whether you want a work-truck blackwall or a more decorative whitewall appearance.

No, 1975 Jeep Truck models do not use the same tire size. The J-10 uses three 15-inch sizes: H78-15, HR78-15, and 10-15. The J-20 uses four different truck sizes: 800-16.5, 950-16.5, 750-16, and 875-16.5. That split reflects the difference between the lighter-duty J-10 and the heavier-duty J-20 rather than a simple styling variation.

For a buyer, that means year and make are only the first step. If you skip the model check, it is easy to end up comparing a 15-inch J-10 tire to a 16.5-inch J-20 tire that cannot mount on the same wheel. Start with the truck’s model badge or VIN research, then verify the wheel diameter already on the truck before narrowing the choice to tread style, sidewall style, or construction.

On a 1975 Jeep Truck J-10, H78-15 is the bias-ply option and HR78-15 is the radial option. The main distinction is construction, not a change from one wheel diameter to another, since both are 15-inch fitments. Bias-ply tires keep a more traditional period character, while a radial-format choice is usually the one buyers consider when they want a later-style driving feel on the road.

The practical decision comes down to how you use the truck and how closely you want to mirror period practice. A restoration-minded J-10 often stays with the bias-ply route, especially when sidewall appearance is part of the goal. A truck that sees more regular road use may lead its owner toward the radial-format size. Either way, confirm the wheel diameter and your preferred look before moving on to the individual tire.

Sidewall style varies quite a bit across 1975 Jeep Truck sizes. H78-15 is available in both Wide Whitewall and Blackwall form, while 750-16 is also offered in both Blackwall and Wide Whitewall versions. The J-20’s 800-16.5, 950-16.5, and 875-16.5 truck sizes are blackwall applications in the products available here, which suits the heavy-duty character of those fitments.

For most 1975 Jeep Truck owners, blackwall is the more natural visual match, especially on J-20 work-oriented trucks. Whitewalls can make sense when the goal is a more stylized period presentation, especially on a J-10 or on a truck restored with a more personalized look. Once the correct size is confirmed, sidewall style becomes an appearance choice rather than a fitment change, so it is worth deciding how original or how expressive you want the finished truck to look.

Four brands cover the 1975 Jeep Truck sizes here: Coker Classic, STA, Firestone, Lester, and BFGoodrich. H78-15 comes from Coker Classic and STA, 750-16 comes from Firestone, Lester, and BFGoodrich, and the 800-16.5, 950-16.5, and 875-16.5 J-20 truck sizes are handled by STA. Brand coverage follows the size family, so the answer changes depending on whether you have a J-10 or a J-20.

That brand split is useful because it narrows the search quickly. A J-10 owner looking at H78-15 will compare a different set of brands than a J-20 owner working with 16- or 16.5-inch truck tires. It also means appearance choices are broader in some sizes than others, especially where wide whitewalls are offered. The best approach is to identify the exact size first, then compare brands within that one fitment family.

Rim width depends on the size used on the 1975 Jeep Truck. H78-15 fits a 5.50- to 7.00-inch rim, 800-16.5 fits a 6.00- to 6.50-inch rim, 950-16.5 fits a 6.50- to 6.75-inch rim, and 750-16 fits a 5.00- to 6.00-inch rim. Those ranges are size-specific and should not be transferred from one fitment to another, even within the same model family.

That is especially important on a 1975 Jeep Truck because the J-20 spans both 16-inch and 16.5-inch applications, and the acceptable wheel width changes with the tire. Before choosing a tire, measure the wheel or confirm the wheel specification already on the truck. If the vehicle has been modified over the years, treat the actual wheel on the truck as the controlling factor rather than assuming it still carries the original type.

Inner tube status is not marked out uniformly across the 1975 Jeep Truck products here, so tube use should be treated as product-specific rather than assumed by size alone. That matters most with vintage truck applications, where the wheel design and the tire’s own construction details both influence whether a tube is appropriate. A blanket yes-or-no answer across all seven sizes would be too broad for this range.

The safest way to handle a 1975 Jeep Truck is to match the tire to the wheel you actually have and confirm the tire’s sidewall markings before installation. Older multi-piece, riveted, or non-safety-hump wheels may call for a different approach than later tubeless-style rims. If your truck is a restoration or a long-owned work truck with uncertain wheel history, checking the wheel type first will prevent the wrong tube decision.

No, original 1975 Jeep Truck wheels cannot be treated as universal across all sizes because the year-make range uses 15-inch, 16-inch, and 16.5-inch tire diameters. J-10 sizes are 15-inch applications, while J-20 sizes span 16-inch and 16.5-inch wheels. Even before rim width is considered, those diameter differences prevent a single wheel from covering the whole lineup.

For that reason, wheel verification should happen before brand or sidewall comparisons. A truck wearing 16.5-inch wheels must stay within the 16.5-inch family unless the wheels themselves are changed, and the same principle applies to 15- and 16-inch applications. On an older Jeep pickup that may have had decades of service parts and wheel swaps, confirming the wheel stamp or physically measuring the wheel is time well spent.

A 1975 Jeep Truck should be stored in a cool, dry, dark space away from direct sunlight, electric motors, battery chargers, furnaces, and other ozone-producing equipment. Keep the tires clean, maintain proper inflation, and move the truck periodically so one section of the tread is not carrying the load for months at a time. Bias-ply tires, which make up most of this year’s fitments, are more prone to temporary flat-spotting during long static storage than radials.

If the truck will sit for an extended season, many collectors either roll it a short distance every few weeks or support it carefully to reduce constant load on the tires. That matters on a heavy pickup more than on a light compact car. Storage habits do not just protect tread and sidewalls; they also help the truck drive more smoothly when it returns to the road after a long layup.

Tires on a 1975 Jeep Truck should be judged more by age and condition than by mileage. A collector or hobby truck may accumulate very few miles, yet the rubber still ages from time, heat cycles, ozone, and storage conditions. A sensible rule is to begin evaluating tires closely around the five- to seven-year point and to treat about ten years as a serious replacement threshold, regardless of remaining tread depth.

The date code on the tire is the place to start, followed by a close look at sidewall cracking, tread separation signs, hardening, and how well the tire holds pressure. This is especially important on a vintage truck because age-related tire issues can appear long before the tread looks worn out. A low-mileage 1975 Jeep Truck can still need new tires simply because time has done what miles did not.

Tires on a 1975 Jeep Truck deserve a quick inspection before every drive and a more thorough inspection before any extended outing. Check inflation, look for visible cracking, bulges, cuts, embedded debris, and irregular wear, and make sure the truck is not developing a slow leak. On older vehicles, it is also wise to inspect the spare, since many collector trucks carry a spare that has aged longer than the road tires.

A walk-around takes only a few minutes and can catch the issues that matter most on a vehicle of this age. If your truck uses a tube-type setup or older-style valve hardware, include the valve stems and surrounding area in the check rather than focusing on the tread alone. Frequent inspection is cheap insurance on a 1975 Jeep Truck because these vehicles often alternate between long periods parked and sudden longer drives.

For a 1975 Jeep Truck Truck J-10, period-correct fitment centers on the sizes used on that model: H78-15, HR78-15, and 10-15. By the mid-1970s, Jeep trucks sat in a transition era where bias-ply construction was still common and radial options were becoming more familiar, which is why both a bias-ply H78-15 and a radial-format HR78-15 appear in the J-10 range. No single original-equipment brand should be assumed without checking factory literature for the exact truck.

That means a restoration should start with the truck’s intended finish standard. If you want a highly original presentation, construction type and sidewall style matter almost as much as the size itself. If the truck has unusual trim, export-market history, or dealer-installed equipment, a Jeep marque club or factory brochure is the right place to confirm what would have been most authentic for that exact vehicle.

Correct tire fitment absolutely matters when a 1975 Jeep Truck is judged for authenticity. Judges and knowledgeable enthusiasts typically notice whether the size matches the model, whether the construction type looks era-appropriate, and whether the sidewall style suits the truck’s intended presentation. A J-20 on the wrong wheel diameter or a heavily stylized sidewall on a work-truck restoration can stand out quickly to people familiar with full-size Jeeps.

The level of importance depends on the event. Local casual shows may reward overall condition more than technical correctness, while marque or concours-style judging often pays close attention to size, construction, and sidewall appearance. If your truck is being prepared for a judged class, verify the event’s standards ahead of time and compare them with Jeep club guidance so the tire choice supports the rest of the restoration rather than working against it.

On the 1975 Jeep Truck J-20 sizes where both appear, STA Traxion and STA Super Transport share the same basic fitment but differ in series and, in some cases, weight. In 800-16.5, the Super Transport carries a 2045-pound load rating at 60 psi and weighs 33 pounds, while the Traxion weighs 31 pounds. In 950-16.5, both carry a 2780-pound load rating at 60 psi, with the Traxion at 40 pounds and the Super Transport at 41 pounds.

Those differences matter less as a question of fit and more as a question of the truck’s intended character. A buyer restoring a more utilitarian J-20 may prefer one series over the other for its period truck personality, while another may focus on the exact size and load figure first. Since both are blackwall J-20 truck tires in the correct wheel diameter family, the comparison should be made within the confirmed size rather than across the whole model range.

A 1975 Jeep Truck can be safely driven on the highway when the tires are the correct size for the model, are in sound condition, and are inflated and mounted properly. Most of the sizes here are traditional bias-ply truck applications, while the J-10 also includes a radial-format HR78-15 option. No speed ratings are marked in the available size designations here, so the practical limit on highway travel is often as much about the truck’s age, suspension, steering, and braking condition as it is about the tire itself.

That does not mean highway use is off the table; it means expectations should match the vehicle. A well-sorted 1975 Jeep Truck used within normal cruising speeds is a very different situation from sustained high-speed interstate running with old suspension components or unknown wheel history. Before longer highway use, verify tire age, condition, balance, pressure, and wheel integrity so the tire choice supports the rest of the truck’s mechanical condition.

Inflation pressure on a 1975 Jeep Truck depends on the exact size and tire chosen. H78-15 appears at 1770 pounds at 32 psi and also at 1830 pounds at 45 psi depending on the product. 800-16.5 reaches 2045 pounds at 60 psi, 950-16.5 reaches 2780 pounds at 60 psi, and 750-16 appears at 1660 pounds at 40 psi or 1850 pounds at 48 psi depending on the tire. Those figures belong to those individual sizes and tires only.

For actual service pressure, use the truck manufacturer’s recommended pressure as the starting point for the vehicle and compare it with the tire manufacturer’s pressure guidance for the exact tire you are running. Do not assume that a higher maximum pressure should always be used in normal driving. Load carried, front-to-rear weight distribution, and the specific tire all affect the correct real-world setting on a vintage Jeep pickup.

Before a longer drive in a 1975 Jeep Truck, inspect all four tires and the spare for cracking, cuts, bulges, abnormal wear, and proper inflation. Confirm that each tire is the correct size for the truck’s model and wheel diameter, and check the valve stems and wheel condition at the same time. A longer outing is also the right moment to look for any sign of a slow leak or uneven wear pattern that might point to a wheel, alignment, or suspension issue.

Because the truck itself is now decades old, the tire check should be part of a broader pre-drive routine rather than a stand-alone step. Wheel bearings, brakes, steering play, shocks, and lug torque all matter on an older full-size pickup, especially one that may spend more time parked than driven. When the tires and the chassis are both ready, a 1975 Jeep Truck is far better prepared for a longer trip.