GMC Trucks S15 Tires

GMC Trucks S15 uses six tire sizes across the 1982 to 1990 range: 195/75R14 and 205/75R14 on 14-inch wheels; 195/75R15, 205/75R15, 235/75R15, and 215/65R15 on 15-inch wheels. The 14-inch sizes appear in 1982 and again from 1984 through 1990. The 15-inch sizes begin in 1983, with 195/75R15 and 235/75R15 used through 1988, 205/75R15 appearing in 1983 and 1988, and 215/65R15 appearing from 1988 through 1990.

The key is to identify both the model year and the wheel diameter on the actual truck before narrowing the choice. Several years overlap multiple sizes, so the right fit is determined by the truck’s specific configuration rather than the S15 name alone. Once the wheel diameter is confirmed, compare the current tire size, wheel width, and overall stance so the replacement stays consistent with how the truck is set up.

The 1988 GMC Trucks S15 has six listed sizes because that year includes both 14-inch and 15-inch wheel applications as well as multiple tire widths and profiles. The 14-inch choices are 195/75R14 and 205/75R14, while the 15-inch choices are 195/75R15, 205/75R15, 215/65R15, and 235/75R15. That kind of spread usually reflects different trim, suspension, appearance, or package combinations within the same model year.

A 1988 truck cannot be matched accurately by year alone. Start by checking whether the wheels are 14-inch or 15-inch, then compare the current tire size on the sidewall to the year listing. If the truck has been changed from its original wheels, use the actual wheel diameter and width as the deciding factor rather than assuming every 1988 S15 used the same tire.

GMC Trucks S15 uses both 14-inch and 15-inch rim diameters across this production range. The earliest year listed, 1982, uses 14-inch sizes, while 15-inch sizes appear in 1983 and continue alongside 14-inch fitments in later years. The 14-inch tire sizes are 195/75R14 and 205/75R14, and all of the other listed sizes use 15-inch wheels.

Wheel diameter is the first fitment checkpoint because a 14-inch tire will not fit a 15-inch wheel and vice versa. Read the last number in the tire size code to confirm it, or measure and verify the wheel if the truck has aftermarket or swapped rims. Once the diameter is settled, use the year listing to narrow the correct width and profile for that specific S15.

A 1986 GMC Trucks S15 can use 195/75R14, 205/75R14, 195/75R15, or 235/75R15, so the correct size depends on the specific wheel and configuration on the truck. The 14-inch options are 195/75R14 and 205/75R14, while the 15-inch options are 195/75R15 and 235/75R15. That means there is no single 1986 answer without checking the truck itself.

Begin with the tire currently mounted on the truck, then verify the wheel diameter and width before replacing anything. If the truck has been restored, lowered, or changed from stock, the size on the sidewall may tell you more than the model year alone. Matching the existing setup is usually the best path unless you are intentionally returning the truck to a different period-correct configuration.

GMC Trucks S15 tires in these sizes are offered in several sidewall styles, including narrow whitewall, wide whitewall, redline, goldline, RWL, and OWL. The selection varies by size. The whitewall choices are especially broad in the 14-inch and 15-inch passenger-style sizes, while 235/75R15 and 215/65R15 also include raised-letter and performance-oriented sidewall options.

Sidewall style affects the truck’s visual character as much as the size itself. A whitewall can suit a restored or custom presentation, while RWL or OWL sidewalls fit a more sporty or truck-forward 1980s look. Once the correct size is established, choose the sidewall treatment that matches the truck’s era, trim theme, and intended appearance rather than treating all options as visually interchangeable.

GMC Trucks S15 tires in this range are available from Coker Classic, Tornel, Maxxis, Travelstar, American Classic, BFGoodrich, Goodyear, Cooper, and Coker Classic-branded Custom Cruiser offerings. Brand availability depends on the size. Some sizes lean heavily toward whitewall and period-style brands, while others include more truck or performance-flavored options.

Brand choice matters most after the size and wheel diameter are settled. At that point, compare the sidewall style, tire series, and rim-width compatibility that best matches how the S15 is being restored, customized, or driven. For many owners, the deciding factor is whether the truck calls for a restrained OE-style look, a custom whitewall presentation, or an 1980s raised-letter appearance.

GMC Trucks S15 tire offerings include several distinct series such as Star Series, Coker Classic Radial, American Classic Radial, Silvertown Radial, Tornel Classic, Classic Whitewall MA-1, UN106, All Terrain T/A KO2, Eagle GT, Cobra Radial G/T, and Radial T/A. All of them are radial tires, but they differ in appearance, intended character, and sidewall treatment. Some lean toward period whitewall styling, while others use redline, goldline, raised white letters, or all-terrain presentation.

The practical way to use series differences is to decide what kind of S15 you are building or preserving. A stock-looking or custom cruiser truck may favor one of the whitewall radial series, while a sportier or more truck-oriented setup may point toward Radial T/A, Eagle GT, Cobra Radial G/T, or KO2-style choices where available. Select the series only after confirming the exact size that belongs on the truck.

A GMC Trucks S15 should be stored in a cool, dry, dark space with the tires kept away from direct sunlight, electric motors, ozone sources, and petroleum contamination. Tires age from time and environment as much as from mileage, and collector or low-use trucks often spend long periods parked. Clean, stable conditions help preserve both the rubber and the appearance of specialty sidewalls.

Set the tires to the appropriate inflation level for storage, move the truck occasionally to avoid flat-spotting, and avoid leaving the full vehicle weight on one contact patch for months at a time. If the S15 will sit for a long season, many owners use tire cradles or place the vehicle on stands while supporting the suspension properly. Good storage habits do more for tire life than many buyers expect.

Tires on a GMC Trucks S15 should be inspected before regular road use and at scheduled intervals even if the truck is driven only occasionally. Look for cracking, bulges, sidewall damage, uneven wear, low inflation, and signs that the tread is aging out rather than wearing out. Low-mileage collector trucks can appear fine at a glance while the tires are quietly aging.

A seasonal inspection schedule works well for many S15 owners, with an additional check before any highway trip or long drive. Pay close attention if the truck has sat for extended periods, wears older specialty tires, or has custom wheels that may place the tire near the edge of its recommended rim-width range. Catching age or inflation issues early helps preserve ride quality and prevents avoidable failures.

Tires on a GMC Trucks S15 should be replaced when age, cracking, internal degradation, or structural damage becomes a concern, even if the tread still looks deep. Collector vehicles often accumulate far less mileage than modern daily drivers, so tread depth alone is not a reliable measure of tire health. Sidewall checking, repeated air loss, hardening rubber, and vibration are common warning signs.

Use the tire’s actual condition and age as the deciding factors, not appearance alone. A truck that is driven sparingly can still be riding on tires that are well past their safe service life. If there is any doubt about an older tire’s integrity, especially on a restored or low-use S15, a specialist inspection is the prudent next step before more road miles are added.

The listed GMC Trucks S15 tires are modern radial products intended for road use when they are properly matched to the correct size, wheel diameter, and rim-width range. Safety depends on choosing the right fitment and keeping the tire in sound condition with correct inflation. A properly fitted 14-inch or 15-inch radial is far more important than simply choosing a tire that looks appropriate.

Before road use, confirm that the installed tire size matches the wheel diameter and that the wheel width falls within the tire maker’s stated range where given. Also inspect the age and condition of the tire, especially on trucks that have been stored or driven very little. Public-road safety comes from the whole combination working together: tire, wheel, inflation, suspension condition, and intended use.

Before driving a GMC Trucks S15, check tire inflation, sidewall condition, tread condition, and the wheel diameter stamped into the size so you know the tire actually matches the rim. On this model, that matters because both 14-inch and 15-inch fitments were used across the years. Also confirm that there are no visible cuts, bulges, or signs of old impact damage.

It is also wise to look at overall vehicle readiness rather than viewing the tires in isolation. A compact pickup that has spent time parked may have brake, steering, or suspension issues that affect how the tires behave once moving. A brief inspection before every drive is especially worthwhile on an older S15 because age-related problems often show up after sitting, not after heavy mileage.

A GMC Trucks S15 should be driven at speeds that are appropriate for the specific modern tire fitted, the condition of the truck, and the way the vehicle is set up. Because the available tires here are radial products in several different series, there is no single blanket speed answer for every S15. Tire condition, inflation, wheel fitment, and the truck’s mechanical health all matter.

For an older compact pickup, moderation is usually the right approach unless every part of the combination has been thoroughly checked and the truck is in strong operating condition. Fresh, properly fitted tires can improve confidence, but they do not cancel out the limits of an aging chassis or neglected suspension. Let the truck’s overall condition set the pace, not just the fact that it has new tires.