1986 GMC Trucks S15 Tires

A 1986 GMC Trucks S15 can use 195/75R14, 205/75R14, 195/75R15, or 235/75R15, depending on the sub-model. The 4x2 uses 195/75R14 or 205/75R14, the 4x2 H.D. uses 205/75R14, the 4x4 uses 195/75R15, and the 4x4 (Off-Road) uses 235/75R15. All covered fitments are radial.

The important next step is matching the truck's exact configuration and wheel diameter before selecting a tire. A 14-inch S15 should stay within the 14-inch fitments, while a 15-inch truck needs one of the 15-inch sizes tied to its sub-model. If the truck has changed wheels over the years, verify the actual wheel size and clearance rather than relying on appearance alone.

The 1986 GMC Trucks S15 uses either a 14-inch or 15-inch rim, depending on the sub-model and tire size. The 195/75R14 and 205/75R14 fitments use 14-inch rims, while the 195/75R15 and 235/75R15 fitments use 15-inch rims. Rim diameter is tied directly to the tire size itself.

That makes wheel confirmation one of the first checks before buying tires for an S15. A tire built for a 14-inch rim will not mount correctly on a 15-inch wheel, and the reverse is also true. If the truck has aftermarket wheels or a replaced axle package, inspect the wheel stamping or measure the rim rather than assuming the original setup is still in place.

The 1986 GMC Trucks S15 has more than one tire size because the covered range includes different sub-models with different roles. Two-wheel-drive, heavy-duty two-wheel-drive, standard four-wheel-drive, and off-road four-wheel-drive versions do not all share the same wheel and tire package, so fitment changes across the lineup.

That means tire selection starts with vehicle identification, not sidewall style or brand. Once the correct sub-model and wheel diameter are confirmed, the choice becomes much simpler because each setup narrows to the size or sizes that belong on that version. This is especially important on older trucks that may have received replacement wheels, suspension changes, or cosmetic updates over time.

Start with the correct tire size for the exact 1986 GMC Trucks S15 sub-model, then confirm the wheel diameter matches that size. After that, compare construction, sidewall style, rim-width compatibility, and the overall look you want, since available S15 tires range from traditional whitewalls to redline and raised white letter designs in some sizes.

A truck kept close to stock often benefits from staying within its original size family and choosing a sidewall treatment that matches the vehicle's character. A more utility-focused or modified truck may call for different priorities, such as checking wheel width or load figures more closely. Looking at those factors together helps narrow the best match without turning the decision into guesswork.

Sidewall choices for the 1986 GMC Trucks S15 include narrow whitewall, wide whitewall, redline, and raised white letter styles, depending on the tire size. The broadest style variety appears in 205/75R14, while 235/75R15 includes both whitewall options and an RWL truck-oriented choice. Smaller size groups are more limited but still offer appearance differences.

That gives the S15 owner room to tailor the truck's presentation without changing the underlying fitment. A whitewall can lean more restoration-oriented or custom, redline adds a sportier vintage look, and raised white letter sidewalls suit a more truck-style appearance. The key is choosing the look within the size that belongs on the truck rather than selecting a style first and forcing fitment afterward.

Tires for the 1986 GMC Trucks S15 are available from Coker Classic, American Classic, BFGoodrich, Maxxis, Tornel, and Travelstar, depending on size. Brand availability is not identical across all four sizes, so a 14-inch fitment and a 15-inch fitment may present very different product mixes in both series and sidewall treatment.

That matters because brand choice is only one part of the decision. Once the correct size is confirmed, compare which brands offer the sidewall style, tire series, and wheel-width compatibility that suit the truck. Some sizes open the door to more visual variety, while others are narrower in selection, so the best comparison happens inside the correct fitment rather than across the whole S15 range.

A period-style 1986 GMC Trucks S15 usually starts with keeping the correct size for the truck's exact sub-model, then choosing a sidewall treatment that suits the look you want. Whitewall options are available in all covered sizes, and some fitments also offer redline or raised white letter styling that can shift the truck's overall presentation.

For a restoration-oriented truck, size and wheel diameter matter first because the right proportions do more for appearance than any brand name alone. After that, sidewall width and tire series help fine-tune the look. If exact originality matters beyond a general period-style appearance, compare the truck against marque references, photos, or build documentation before settling on one visual treatment.

On the 1986 GMC Trucks S15, the covered primary fitments are all radial, so the appearance differences come more from size and sidewall style than from choosing between radial and bias-ply construction. A narrow whitewall, wide whitewall, redline, or raised white letter sidewall can noticeably change how the truck reads from the curb.

That makes visual selection especially important on a restored or carefully presented S15. A truck with a simple two-wheel-drive stance may call for a different sidewall look than an off-road 4x4 using 235/75R15. Staying with the correct fitment for the sub-model preserves the truck's proportions, while the sidewall treatment lets the owner lean more stock-style, custom, or truck-oriented in appearance.

Yes, modifications can affect tire fitment on a 1986 GMC Trucks S15 even when the tire size itself is one of the covered S15 fitments. Changes such as aftermarket wheels, altered wheel width, suspension lifts or lowering, and body or steering components can change how much room the tire has at full lock or full suspension travel.

An S15 that no longer has its original wheel and suspension setup should be checked carefully before new tires are installed. Confirm the wheel diameter and width, then inspect clearance at the fender, inner wheelhouse, and steering components. That matters most on the 15-inch 4x4 and off-road sizes, where overall tire dimensions are larger and tolerance for changes may be tighter.

Before driving a 1986 GMC Trucks S15 on new tires, inspect the wheels for the correct diameter and condition, check that the tires are inflated properly, and make sure there is no rubbing at the fenders, suspension, or steering components. It also helps to confirm lug hardware, valve stems, and overall wheel mounting condition before the first road test.

A short, careful drive is the right follow-up after installation. Listen for rubbing, feel for vibration, and recheck pressure once the truck has settled into normal use. On an older pickup, it is also wise to inspect alignment-related wear items such as steering and suspension components, since new tires can reveal issues that worn tires had been masking.

Tires on a 1986 GMC Trucks S15 should be inspected regularly, especially if the truck is driven infrequently or stored for long periods. Look over tread wear, sidewall cracking, cuts, bulges, and any sign of air loss, and include the spare if the truck still carries one. Older collector-era trucks often age tires out before they wear them out.

A quick visual check before each drive and a more thorough inspection at routine service intervals is a sensible pattern. Pressure should be monitored consistently, since an underinflated tire can change wear and handling long before obvious damage appears. Storage conditions matter too, so keeping the truck away from prolonged sun, moisture, and ozone sources helps preserve tire condition between drives.