The 1979 Jeep Truck Truck J-20 comes from the late full-size Jeep era, when heavy-duty pickups were valued for work capacity, rugged drivetrains, and straightforward utility. That background matters when choosing tires, because this J-20 uses 16.5-inch bias-ply truck sizes rather than a modern light-truck radial setup. The primary sizes are 875-16.5 and 950-16.5, both tied to traditional truck-oriented construction. Available choices stay within that vintage bias-ply theme, with blackwall STA options in Traxion, Transport Highway, and Super Transport lines. For a restoration-minded truck or a roadgoing survivor, the real task is confirming which of the two sizes suits the wheel setup and intended use.
Which Tire Size Is Right for The 1979 Jeep Truck Truck J-20
The 1979 Jeep Truck Truck J-20 uses two primary tire sizes, and both are bias-ply designs for 16.5-inch wheels. Because the Base sub-model can be associated with either 875-16.5 or 950-16.5, the first step is confirming which wheel and tire setup is actually on the truck before choosing a replacement. Once that is settled, the decision shifts to tread style, tire series, and whether a more work-focused or highway-oriented bias-ply option makes the most sense.
The 875-16.5 size uses a vintage numeric bias-ply format, where 8.75 refers to the nominal section width in inches and 16.5 is the wheel diameter. On a 1979 Jeep Truck Truck J-20, this keeps the tire selection within a traditional truck-type bias-ply construction rather than a modern radial format. Available choices include STA blackwall tires in the Traxion and Transport Highway series, both aimed at period-style truck use. This size is worth considering when the truck retains its existing 16.5-inch wheel setup and the goal is staying close to a vintage heavy-duty tire presentation.
The 950-16.5 size is another vintage numeric bias-ply truck size, with the leading number indicating a nominal 9.50-inch section width and the final number identifying the 16.5-inch rim. For the 1979 Jeep Truck Truck J-20, it represents a larger bias-ply fitment choice within the same wheel diameter family. STA offers this size in blackwall Traxion and Super Transport versions, with truck-oriented specifications including a 2780@60 psi maximum load figure and a 6.50 to 6.75 inch rim-width range. It deserves a closer look when the truck is already set up for this wider 16.5-inch bias-ply configuration.
Sub-model fitment is simple here because the covered 1979 Jeep Truck Truck J-20 Base is associated with the same two primary tire-size paths used on this page. What matters most is confirming which of those two sizes is on the truck now, since replacement choice depends more on the existing wheel and tire setup than on trim distinction.
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1979 Jeep Truck Truck J-20 Base
The 1979 Jeep Truck Truck J-20 Base can use either of the page's bias-ply 16.5-inch tire sizes, so the key detail is the truck's current wheel-and-tire combination. That means tire selection should start with size confirmation, then move to the preferred STA series and the kind of period-style truck use the vehicle is expected to see.
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.
Best 1979 Jeep Truck Truck J-20 Tires for Sale
Available 16.5-inch J-20 tires stay within a traditional bias-ply truck format, with STA blackwall choices across the Traxion, Transport Highway, and Super Transport series. Comparing the product grid comes down to size, series character, and details such as rim-width and load specifications where they apply.
These FAQs focus on the two 16.5-inch tire sizes used on the 1979 Jeep Truck Truck J-20, along with wheel confirmation, bias-ply selection, period-style appearance, and the road-use checks that matter on an older heavy-duty pickup.
Tire Size & Fitment
What tire size fits a 1979 Jeep Truck Truck J-20?
The 1979 Jeep Truck Truck J-20 uses two primary tire sizes: 875-16.5 and 950-16.5. Both are bias-ply truck tires built for 16.5-inch wheels, and the covered J-20 Base can be associated with either size rather than one universal fitment.
That makes size confirmation the first step before ordering tires. Check the size already mounted on the truck, then confirm the wheel diameter is 16.5 inches and that the wheel setup has not been changed over the years. On an older pickup, replacement choice depends as much on the actual wheel-and-tire combination currently in service as it does on the model name.
What size rim does a 1979 Jeep Truck Truck J-20 use?
The tire fitments for the 1979 Jeep Truck Truck J-20 use a 16.5-inch rim diameter. Both 875-16.5 and 950-16.5 are tied to that same wheel diameter, so the main difference between the two fitments is the tire size itself rather than the rim diameter family.
A 16.5-inch wheel should not be confused with a 16-inch wheel, even though the numbers are close. Before choosing replacement tires, verify the wheel stamping or measure carefully if the truck has been modified or inherited with unknown wheels. On the 950-16.5 products, rim-width specifications are also relevant, so wheel width deserves attention along with diameter.
What does 875-16.5 mean on a 1979 Jeep Truck Truck J-20?
On a 1979 Jeep Truck Truck J-20, 875-16.5 is a numeric bias-ply size. The 8.75 portion refers to the tire's nominal section width in inches, and 16.5 identifies the wheel diameter. It is an older truck sizing system, not a modern metric radial size.
Understanding that format helps keep replacement decisions on track, especially when a truck has seen decades of service and possible wheel changes. A buyer comparing vintage truck tires should also confirm whether the J-20 is running the narrower 875-16.5 setup or the larger 950-16.5 setup, since both belong to the same wheel diameter but represent different tire dimensions.
Choosing the Right Tire
What should I consider when choosing a 875-16.5 or 950-16.5 tire for a 1979 Jeep Truck Truck J-20?
Start with the correct primary size, because the 1979 Jeep Truck Truck J-20 can use either 875-16.5 or 950-16.5. After that, compare the construction, tire series, and any product details that affect how the truck will be used, such as highway-oriented versus more traction-focused tread character.
The next step is checking the wheel itself rather than choosing by appearance alone. Confirm the wheel is 16.5 inches in diameter, and on 950-16.5 products pay attention to the stated 6.50 to 6.75 inch rim-width range. On a heavy-duty vintage pickup, matching the tire to the existing wheel setup matters just as much as selecting the right series.
What brands offer tires for the 1979 Jeep Truck Truck J-20?
The available tires for the 1979 Jeep Truck Truck J-20 come from STA. Within the two J-20 sizes on this page, STA covers the range with several vintage truck bias-ply offerings rather than mixing multiple brands across the fitment.
That means the real comparison is not brand versus brand, but one STA series versus another. A buyer can focus on whether the truck needs 875-16.5 or 950-16.5 first, then compare the Traxion, Transport Highway, or Super Transport lines by intended use, appearance, and any wheel-spec details tied to the specific size being considered.
What tire series are available for the 1979 Jeep Truck Truck J-20?
The 1979 Jeep Truck Truck J-20 is covered here by STA's Traxion, Transport Highway, and Super Transport series. The 875-16.5 size is available in Traxion and Transport Highway, while the 950-16.5 size is available in Traxion and Super Transport.
Those series names matter because they give the buyer a way to compare tire character within the correct vintage bias-ply size. Once the truck's actual tire size is confirmed, the series choice becomes the next decision point. It is also useful to compare supporting details such as weight, rim-width specification where stated, and the kind of period-style truck presentation the owner wants to maintain.
Restoration & Appearance
Which tire should I choose for a period-style 1979 Jeep Truck Truck J-20?
A period-style 1979 Jeep Truck Truck J-20 usually starts with staying in the correct vintage-style bias-ply size family: 875-16.5 or 950-16.5, depending on the truck's actual setup. The available STA choices preserve that traditional heavy-duty truck presentation better than switching to an unrelated modern sizing format.
The right selection depends on how closely the truck is being restored and which wheel-and-tire combination it currently carries. Owners seeking a more historically consistent appearance should verify the wheel diameter and the size already in use before making a change. When exact originality matters, period photos, marque-club references, and vehicle-specific history are worth checking alongside the tire choice.
How does tire construction affect the appearance of a restored 1979 Jeep Truck Truck J-20?
Tire construction has a visible effect on a restored 1979 Jeep Truck Truck J-20 because both primary fitments here are bias-ply truck tires. That construction supports the traditional shape and stance many owners expect on a late-1970s heavy-duty Jeep pickup running 16.5-inch vintage-style tires.
Appearance is not only about construction, though. Sidewall treatment and tread style also shape the truck's finished look, and the options here stay within a blackwall truck presentation. For a restoration-minded owner, keeping the correct size family and construction type aligned with the existing wheel setup usually matters more than chasing a tire that merely looks close at first glance.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 1979 Jeep Truck Truck J-20?
Yes, modifications can affect tire fitment on a 1979 Jeep Truck Truck J-20 even when the tire size itself is correct. Aftermarket wheels, suspension changes, altered ride height, or body modifications can change the space available around a 875-16.5 or 950-16.5 tire.
That is especially important on an older truck that may have changed hands several times. Confirm wheel diameter first, then look at wheel width, steering clearance, and fender or suspension clearance before settling on a replacement. A truck wearing non-original wheels or stance changes should always be inspected as it sits now rather than judged only by factory-era fitment references.
What should I inspect before driving a 1979 Jeep Truck Truck J-20 on new tires?
Before driving a 1979 Jeep Truck Truck J-20 on new tires, inspect the wheels, valve stems, lug hardware, and general clearance around the tires at full steering lock and normal ride height. It is also smart to look over the suspension and steering components, especially on a heavy-duty vintage pickup.
After installation, verify that inflation matches the tire's service needs and keep an eye on early wear or rubbing signs during the first miles. A road-ready check should also include the condition of the spare if one is carried. On an older truck, fresh tires perform best when the surrounding wheel, brake, and steering hardware is equally ready for use.
How should 875-16.5 or 950-16.5 tires on a collector 1979 Jeep Truck Truck J-20 be maintained?
Collector-use 875-16.5 and 950-16.5 tires on a 1979 Jeep Truck Truck J-20 should be inspected regularly for air loss, tread wear, cuts, bulges, and sidewall cracking. A truck that sits for long periods still needs routine pressure checks, because age and storage conditions can affect tire condition even when mileage stays low.
Storage habits matter just as much as inspection. Keep the J-20 away from prolonged heat, direct sunlight, excess moisture, and ozone sources such as electric motors or battery chargers. It also helps to move the truck periodically so the tires are not parked in the same position for extended stretches, especially on a heavy-duty vehicle with substantial static weight.
