The 2018 GMC Trucks Sierra 3500 HD sits in the heavy-duty pickup world where towing, hauling, and work-focused trim differences matter just as much as appearance. This is a modern HD truck, but tire selection is still very configuration-specific because single-rear-wheel and dual-rear-wheel versions do not share the same size. The Sierra 3500 HD uses radial tires, with 235/80R17 tied to DRW applications and 265/70R18 used on several non-DRW trims. That makes wheel diameter the first checkpoint, followed by confirming the exact sub-model. For owners replacing worn tires, the real goal is matching the truck's existing wheel setup and intended use before choosing among the available options.
Which Tire Size Is Right for The 2018 GMC Trucks Sierra 3500 HD
Two tire sizes apply to the 2018 GMC Trucks Sierra 3500 HD, and they are split by sub-model and wheel diameter. Both are radial fitments, but one uses a 17-inch rim and the other uses an 18-inch rim, so confirming the exact sub-model and existing wheel size is the first step before comparing tire choices.
A 235/80R17 uses a 235-millimeter section width, an 80-series aspect ratio, radial construction, and a 17-inch rim. On the 2018 GMC Trucks Sierra 3500 HD, this size belongs to DRW configurations, making it a fitment tied to the truck's heavier-duty wheel setup rather than to every version of the model. Available product choice in this size includes a BFGoodrich All-Terrain T/A KO2 with an RBL sidewall and All Terrain TA KO2 series branding. This size should be evaluated by owners who have confirmed a dual-rear-wheel Sierra 3500 HD and want to match the truck's existing 17-inch wheel arrangement.
A 265/70R18 uses a 265-millimeter section width, a 70-series aspect ratio, radial construction, and an 18-inch rim. On the 2018 GMC Trucks Sierra 3500 HD, this size is used on several non-DRW trims, so it is tied to the truck's single-rear-wheel configuration and 18-inch wheel package. The key decision here is less about construction type and more about confirming that the truck has the correct 18-inch wheels and the matching sub-model setup. This size is the right place to start for Base, Denali, SLE, SLT, and Snow Plow Prep Package versions that are not marked DRW.
Sub-model fitment on the 2018 GMC Trucks Sierra 3500 HD is not universal, because DRW versions use a different tire size and rim diameter than non-DRW trucks. Checking the exact sub-model matters first, especially if the truck has work-package equipment or dual rear wheels.
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2018 GMC Trucks Sierra 3500 HD (DRW)
The DRW version uses the 235/80R17 radial fitment tied to its 17-inch wheel setup. Tire selection starts with confirming the dual-rear-wheel configuration, then comparing products suited to that size and intended truck use.
The Base model uses the 265/70R18 radial size on an 18-inch rim. That makes wheel confirmation straightforward, and the next step is choosing a tire that matches how the truck is actually driven and loaded.
The Denali uses the 265/70R18 radial fitment rather than the 17-inch DRW size. Tire selection for this sub-model centers on keeping the correct 18-inch size and then weighing tread style, appearance, and use priorities.
The SLE uses the 265/70R18 radial setup in its non-DRW form. For replacement tires, the important point is confirming the truck is not the DRW version before moving on to product and usage preferences.
The SLE (DRW) switches to the 235/80R17 radial size used by dual-rear-wheel Sierra 3500 HD models. That means the 17-inch wheel package drives the tire decision, not the standard SLE fitment.
2018 GMC Trucks Sierra 3500 HD SLE Snow Plow Prep Pkg.
The SLE Snow Plow Prep Package without DRW uses 265/70R18 radial tires. Buyers should confirm that the truck retains its 18-inch wheel setup, especially if it has seen work-truck modifications over time.
2018 GMC Trucks Sierra 3500 HD SLE Snow Plow Prep Pkg. (DRW)
The DRW Snow Plow Prep SLE uses the 235/80R17 radial size instead of the 18-inch single-rear-wheel fitment. That makes configuration verification essential before choosing a replacement tire for work use or seasonal duty.
The SLT uses the 265/70R18 radial size on 18-inch wheels. Replacement tire shopping is mainly about staying with the correct wheel diameter and selecting a tire style that suits road use, towing, or mixed-duty driving.
The SLT (DRW) uses the 235/80R17 radial fitment associated with the truck's dual-rear-wheel setup. That keeps the focus on the correct 17-inch size and on products appropriate for heavy-duty service.
2018 GMC Trucks Sierra 3500 HD SLT Snow Plow Prep Pkg.
The SLT Snow Plow Prep Package in non-DRW form uses 265/70R18 radial tires. This sub-model should be matched to the existing 18-inch wheel package before comparing tire features or tread character.
2018 GMC Trucks Sierra 3500 HD SLT Snow Plow Prep Pkg. (DRW)
The DRW version of the SLT Snow Plow Prep Package uses the 235/80R17 radial size. Tire selection here should follow the dual-rear-wheel layout first, then the truck's actual duty cycle and wheel condition.
2018 GMC Trucks Sierra 3500 HD Snow Plow Prep Pkg.
The Snow Plow Prep Package without DRW uses 265/70R18 radial tires. Owners should confirm the truck remains on its 18-inch wheel setup, particularly if it has been outfitted for commercial or seasonal work.
2018 GMC Trucks Sierra 3500 HD Snow Plow Prep Pkg. (DRW)
The DRW Snow Plow Prep Package uses the 235/80R17 radial fitment. Choosing the right tire starts with the dual-rear-wheel 17-inch setup, since that separates it from the non-DRW Snow Plow Prep trucks.
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 2018 GMC Trucks Sierra 3500 HD Tires for Sale
Available product selection is concentrated around the 235/80R17 fitment, with a BFGoodrich All-Terrain T/A KO2 option featuring radial construction, an RBL sidewall, and a 6.0 to 7.5-inch rim-width range. That makes wheel compatibility and intended truck use the main comparison points.
Owners of a 2018 GMC Trucks Sierra 3500 HD usually need to sort out sub-model fitment first, then wheel diameter, tire size, and product selection. The questions below focus on DRW versus non-DRW sizing, rim fitment, and practical checks before road use.
Tire Size & Fitment
What tire size fits a 2018 GMC Trucks Sierra 3500 HD?
The 2018 GMC Trucks Sierra 3500 HD uses either 235/80R17 or 265/70R18 radial tires. The 235/80R17 size belongs to DRW versions, while 265/70R18 is used on several non-DRW trims, including Base, Denali, SLE, SLT, and Snow Plow Prep Package applications without dual rear wheels.
That means the correct answer depends on the truck's exact configuration, not just the model name on the fender. Start by confirming whether the truck is DRW or non-DRW, then verify the wheel diameter already on the vehicle before choosing a replacement tire.
What size rim does a 2018 GMC Trucks Sierra 3500 HD use?
A 2018 GMC Trucks Sierra 3500 HD uses either a 17-inch rim or an 18-inch rim, depending on sub-model. The 235/80R17 tire size uses a 17-inch rim, while the 265/70R18 tire size uses an 18-inch rim.
Rim diameter is the quickest way to narrow down the right tire size on this truck. Since the two fitments do not share the same wheel diameter, checking the existing wheel before ordering tires helps avoid confusion between DRW and non-DRW Sierra 3500 HD setups.
Why does the 2018 GMC Trucks Sierra 3500 HD have more than one tire size?
The 2018 GMC Trucks Sierra 3500 HD has more than one tire size because its fitment changes with the truck's configuration. DRW models use 235/80R17 radial tires, while non-DRW versions use 265/70R18 radial tires.
This is a heavy-duty pickup line with different wheel and rear-axle layouts, so the tire choice follows the hardware on the truck. Identifying the exact sub-model and confirming whether the truck has dual rear wheels is more important than assuming every Sierra 3500 HD uses the same tire.
Choosing the Right Tire
What should I consider when choosing a 235/80R17 tire for a 2018 GMC Trucks Sierra 3500 HD?
A 235/80R17 tire for a 2018 GMC Trucks Sierra 3500 HD should first match a DRW application with 17-inch wheels. In the available selection, this size includes a BFGoodrich All-Terrain T/A KO2 radial with an RBL sidewall, a 6.0 to 7.5-inch rim-width range, and a maximum load capacity of 3,085 lbs @ 80 psi.
Beyond the size itself, compare the tire's intended tread character, wheel-width compatibility, and load-related specifications against how the truck is actually used. A Sierra 3500 HD that sees towing, commercial duty, or rougher surfaces may need different priorities than one used mostly on pavement.
What sidewall styles are available for 2018 GMC Trucks Sierra 3500 HD tires?
The available 235/80R17 product choice for the 2018 GMC Trucks Sierra 3500 HD uses an RBL sidewall. That sidewall style is part of the BFGoodrich All-Terrain T/A KO2 option offered in this fitment.
Sidewall style matters mostly for appearance and how closely the tire matches the truck's desired look, but it should still come after confirming the correct size and wheel diameter. On a heavy-duty truck, the more important practical checks are fitment, load-related specifications, and intended use.
What brands offer tires for the 2018 GMC Trucks Sierra 3500 HD?
BFGoodrich is available in the 235/80R17 fitment for the 2018 GMC Trucks Sierra 3500 HD. The current product choice in that size is the BFGoodrich All-Terrain T/A KO2 radial.
Brand is only one part of the decision on a Sierra 3500 HD. It still makes sense to confirm the truck's exact size, wheel diameter, rim-width compatibility, and use case first, especially since this model range splits fitment between DRW and non-DRW configurations.
Restoration & Appearance
Does correct tire fitment matter for a 2018 GMC Trucks Sierra 3500 HD restoration?
Correct tire fitment still matters on a 2018 GMC Trucks Sierra 3500 HD, even though this is a newer heavy-duty truck rather than an antique restoration project. Keeping the right size with the right wheel diameter preserves the truck's intended stance and avoids mixing DRW and non-DRW fitments.
Appearance on a modern HD truck is usually tied more to correct proportion and trim-appropriate presentation than to vintage sidewall details. A restoration-oriented owner should confirm the exact sub-model, existing wheel setup, and overall visual goal before choosing between available tire styles.
How does tire construction affect the appearance of a restored 2018 GMC Trucks Sierra 3500 HD?
The 2018 GMC Trucks Sierra 3500 HD uses radial construction in its primary fitments, so the appearance question is less about bias-ply versus radial and more about size, stance, and sidewall presentation. Staying with the correct 235/80R17 or 265/70R18 radial size keeps the truck visually consistent with its wheel package.
On a restoration-minded build, an aggressive tread and an RBL sidewall can give the truck a more purposeful look, while the wrong wheel diameter can make the proportions look off immediately. Matching the truck's actual configuration remains the foundation of a clean, credible finished appearance.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2018 GMC Trucks Sierra 3500 HD?
Yes, modifications can affect tire fitment on a 2018 GMC Trucks Sierra 3500 HD. Aftermarket wheels, suspension changes, leveling or lowering kits, and body alterations can all change how a 235/80R17 or 265/70R18 tire sits relative to the wheel opening and steering components.
The first step is confirming the truck's original DRW or non-DRW configuration, then checking the current wheel diameter and width against the tire being considered. Clearance at full steering lock and under load deserves attention, especially on a heavy-duty pickup that may tow or carry equipment.
What should I inspect before driving a 2018 GMC Trucks Sierra 3500 HD on new tires?
Before driving a 2018 GMC Trucks Sierra 3500 HD on new tires, inspect the wheels for damage, confirm the correct tire size, and make sure inflation is set appropriately for the tire in use. It also helps to look over valve stems, tread seating, and any visible clearance around suspension and body components.
A heavy-duty truck places real demands on its tires, so a quick check should also include signs of rubbing, uneven ride height, or hardware issues that may have gone unnoticed with the old set. A short local drive followed by a recheck can catch problems before longer towing or highway use.
How often should tires on a 2018 GMC Trucks Sierra 3500 HD be inspected?
Tires on a 2018 GMC Trucks Sierra 3500 HD should be inspected regularly, especially before towing, hauling, or seasonal work. Watch for uneven tread wear, sidewall cracking, cuts, bulges, punctures, and any loss of air pressure that could point to wheel or valve issues.
This matters even more on a truck that sits for stretches and then returns to heavy service. A visual inspection before longer drives, combined with routine pressure checks and occasional wheel-condition reviews, helps catch problems early and keeps the tire size and wheel setup working as intended.
