The 2018 RAM Trucks 2500 sits in the modern heavy-duty pickup world where towing, payload, and off-pavement confidence all shape tire choice as much as appearance. Depending on sub-model, this truck uses one of four radial sizes: 245/70R17, 285/70R17, 275/70R18, or 285/60R20, so the first step is matching the truck’s exact trim and wheel diameter. The available choices here lean toward BFGoodrich All-Terrain T/A KO2 fitments with raised white letter sidewalls, giving the truck a purposeful all-terrain look. For a work-focused Tradesman, a luxury-trim Laramie Longhorn, or a trail-oriented Power Wagon, correct size and wheel match come before any other tire decision.
Which Tire Size Is Right for The 2018 RAM Trucks 2500
The 2018 RAM Trucks 2500 uses four primary tire sizes, and they vary by sub-model and wheel diameter. Some trims share 18-inch or 20-inch fitments, while others use specific 17-inch setups, so identifying the exact trim and confirming the truck’s current wheel diameter is the first step. Once that is settled, the real decision becomes choosing the right radial tire within that size and load-capable application.
Fit(s): Big Horn, Laramie, Laramie Longhorn, SLT, and Tradesman
Construction: Radial|Rim: 18 in
275/70R18 is a metric radial size in which 275 is the section width in millimeters, 70 is the aspect ratio, R identifies radial construction, and 18 is the wheel diameter in inches. On the 2018 RAM Trucks 2500, this size supports trims that use an 18-inch wheel and keeps the buyer in a modern radial format suited to heavy-duty pickup use. Available product coverage in this size includes a BFGoodrich All-Terrain T/A KO2 with raised white letter styling. It is the right size to evaluate when the truck is equipped with the correct 18-inch wheel and the goal is to stay with the intended trim-level fitment.
Fit(s): Big Horn, Laramie, Laramie Longhorn, Limited, and SLT
Construction: Radial|Rim: 20 in
285/60R20 is a metric radial size where 285 gives the nominal section width in millimeters, 60 gives the profile ratio, R means radial, and 20 identifies the wheel diameter. This size belongs to 20-inch-wheel 2018 RAM Trucks 2500 configurations and should be treated as a distinct fitment from the 17-inch and 18-inch options used on other trims. Its lower-profile format compared with the 70-series sizes makes wheel confirmation especially important before shopping. Buyers should use this size only after verifying that the truck is one of the 20-inch-equipped sub-models or currently retains the proper 20-inch wheel setup.
285/70R17 is a metric radial tire size with a 285-millimeter nominal section width, a 70-series profile, radial construction, and a 17-inch wheel diameter. On the 2018 RAM Trucks 2500, this fitment is tied to the Power Wagon and reflects a wider 17-inch setup than the narrower 245/70R17 used elsewhere. BFGoodrich All-Terrain T/A KO2 options in this size are available with raised white letter sidewalls, and the products vary in load specification and weight. It is the size to focus on when the truck is a Power Wagon or when a current 17-inch wheel package matches this exact fitment.
245/70R17 is a metric radial size in which 245 is the nominal section width in millimeters, 70 is the aspect ratio, R marks radial construction, and 17 is the wheel diameter in inches. On the 2018 RAM Trucks 2500, this size appears on certain Tradesman applications and should not be confused with the wider 285/70R17 also used on a 17-inch wheel. BFGoodrich All-Terrain T/A KO2 coverage in this size includes a raised white letter treatment and a distinct rim-width range. It is the correct size to review when the truck has the narrower 17-inch setup and the wheel width matches the tire’s requirements.
Sub-model fitment matters on the 2018 RAM Trucks 2500 because tire size changes across the range, and some trims can use more than one wheel-and-tire combination. Identifying the exact trim and confirming the truck’s current wheel diameter helps narrow the correct tire size before comparing product options.
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2018 RAM Trucks 2500 Big Horn
The 2018 RAM Trucks 2500 Big Horn uses either an 18-inch or 20-inch radial fitment, so wheel diameter has to be confirmed before choosing a tire. That means the buying decision starts with the truck’s actual wheel setup, then moves to the appropriate radial option for that size.
The 2018 RAM Trucks 2500 Laramie also spans two radial fitments tied to different wheel diameters. Selecting tires for this trim begins with confirming whether the truck carries the 18-inch or 20-inch setup, then comparing the available tire choice within that exact size.
The 2018 RAM Trucks 2500 Laramie Longhorn shares the same two-size fitment pattern used on other upper trims, with radial tires on either 18-inch or 20-inch wheels. Tire selection comes down to matching the current wheel package first, rather than assuming every Longhorn uses the same size.
The 2018 RAM Trucks 2500 Limited uses a single 20-inch radial tire fitment. That makes size identification more straightforward, but the buyer still needs to confirm that the truck retains the correct 20-inch wheel before moving into product selection.
The 2018 RAM Trucks 2500 Power Wagon uses a dedicated 17-inch radial tire size that differs from the narrower 17-inch fitment found on certain Tradesman trucks. Tire selection here is more about choosing the right version within that size and checking load and wheel compatibility than deciding among multiple primary sizes.
The 2018 RAM Trucks 2500 SLT follows the same two-size radial pattern seen on several mainstream trims. The key step is verifying whether the truck is on its 18-inch or 20-inch wheel setup so the tire search stays focused on the correct fitment.
The 2018 RAM Trucks 2500 Tradesman can use either a 17-inch or 18-inch radial tire size, making wheel confirmation especially important on this trim. Once the current setup is verified, the buyer can compare the proper tire option without crossing into a wider or taller fitment meant for another configuration.
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 RAM Trucks 2500 Tires for Sale
Available product choices center on BFGoodrich All-Terrain T/A KO2 fitments in several 17-inch and 18-inch sizes. Across those options, buyers can compare raised white letter sidewalls, radial construction, rim-width requirements, and load-capacity differences that matter on a heavy-duty truck.
These FAQs for the 2018 RAM Trucks 2500 focus on identifying the correct tire size by trim, understanding wheel diameter differences, comparing available all-terrain tire choices, and checking the truck carefully before regular road use.
Tire Size & Fitment
What tire size fits a 2018 RAM Trucks 2500?
The 2018 RAM Trucks 2500 uses four primary radial tire sizes: 245/70R17, 285/70R17, 275/70R18, and 285/60R20. The correct size depends on the exact sub-model and wheel package, since some trims use more than one fitment while others are tied to a single size.
The practical first step is checking the truck’s trim and confirming whether it has 17-inch, 18-inch, or 20-inch wheels. That matters because two of the sizes share a 17-inch rim diameter but differ noticeably in width and overall dimensions, so choosing by wheel diameter alone is not enough.
What size rim does a 2018 RAM Trucks 2500 use?
A 2018 RAM Trucks 2500 can use 17-inch, 18-inch, or 20-inch rims, depending on sub-model and tire size. The 245/70R17 and 285/70R17 fitments use 17-inch rims, 275/70R18 uses an 18-inch rim, and 285/60R20 uses a 20-inch rim.
That makes wheel confirmation one of the most important steps before ordering tires. A truck that has been changed from its original wheel package, or one that shares the same trim name with more than one wheel option, should be checked at the wheel itself so the tire size and rim diameter stay matched.
Do all 2018 RAM Trucks 2500 sub-models use the same tire size?
No, 2018 RAM Trucks 2500 sub-models do not all use the same tire size. Big Horn, Laramie, Laramie Longhorn, and SLT can use either 275/70R18 or 285/60R20, Limited uses 285/60R20, Power Wagon uses 285/70R17, and Tradesman can use 245/70R17 or 275/70R18.
That variation means trim identification is just as important as the size molded on the current tire. If the truck has aftermarket wheels or a previous owner changed the setup, compare the installed wheel diameter and tire size together so the replacement stays aligned with the truck’s present fitment.
Choosing the Right Tire
What should I consider when choosing a tire for a 2018 RAM Trucks 2500?
Start with the exact tire size and wheel diameter used on the truck, because the 2018 RAM Trucks 2500 spans four different radial fitments across its trim range. After that, compare the tire’s load-capacity specification, rim-width range, and overall application so the replacement matches how the truck is actually used.
A heavy-duty pickup places more importance on correct load support than many passenger vehicles, so it helps to look beyond the basic size code. Buyers should also consider whether the truck is kept in a stock wheel setup, whether an all-terrain tread style suits the vehicle’s use, and whether the selected tire matches the wheel width already on the truck.
What sidewall styles are available for 2018 RAM Trucks 2500 tires?
The available products for the covered 2018 RAM Trucks 2500 fitments use RWL sidewalls, meaning raised white letters. That sidewall treatment gives the truck a more aggressive all-terrain presentation than a plain blackwall and is part of the character of the BFGoodrich All-Terrain T/A KO2 options shown here.
Sidewall style does not change the need to match the correct tire size, load specification, and wheel diameter. It is mainly an appearance decision once the fitment is right, so a buyer comparing products should treat the sidewall treatment as a finishing detail rather than the starting point of tire selection.
What brands offer tires for the 2018 RAM Trucks 2500?
The available fitments shown for the 2018 RAM Trucks 2500 are from BFGoodrich. The tire series represented is the All-Terrain T/A KO2, offered in covered 17-inch and 18-inch sizes with radial construction and raised white letter sidewalls.
That means the main comparison here is less about switching between brands and more about selecting the correct size and specification within the BFGoodrich lineup. Checking load capacity, rim-width range, and the truck’s actual wheel diameter will do more to narrow the right choice than brand comparison alone on this page.
Restoration & Appearance
How does tire construction affect the appearance of a 2018 RAM Trucks 2500?
The 2018 RAM Trucks 2500 uses modern radial tire fitments, so the appearance question is usually about tread style, wheel size, and sidewall treatment rather than choosing between vintage constructions. In the available products here, raised white letter all-terrain radials give the truck a bolder, more off-road-oriented look.
Because this is a modern heavy-duty pickup, appearance still needs to stay anchored to the correct trim-level size and wheel diameter. A truck kept close to stock will usually look most coherent when the tire size matches the intended wheel package, while the sidewall style and all-terrain presentation add the visible finishing touch.
Does correct tire fitment matter for a 2018 RAM Trucks 2500 restoration or stock-style presentation?
Yes, correct tire fitment matters because the 2018 RAM Trucks 2500 was offered with multiple wheel-and-tire combinations across its trim range. A stock-style presentation looks more convincing when the truck carries the size and wheel diameter associated with its specific sub-model rather than a mix from another configuration.
That does not mean every truck needs identical cosmetic treatment, but size discipline is still important. Buyers aiming for a clean original-style look should confirm the trim, current wheel package, and sidewall presentation first, then use vehicle-specific references if exact appearance history is especially important.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2018 RAM Trucks 2500?
Yes, modifications can affect tire fitment on a 2018 RAM Trucks 2500. Aftermarket wheels, changes in wheel width or offset, suspension lifts or lowering, and body alterations can all change how a 245/70R17, 285/70R17, 275/70R18, or 285/60R20 tire sits in the truck’s wheel openings.
A truck with non-stock hardware should be checked for steering clearance, fender clearance, and wheel compatibility before replacement tires are chosen. Even when the tire size itself is correct for a RAM 2500 trim, a modified setup can introduce clearance issues that would not exist on a stock wheel and suspension package.
What should I inspect before driving a 2018 RAM Trucks 2500 on new tires?
Before regular road use, inspect the wheel size, lug hardware, tire pressure, and basic tire condition, then confirm that the new tires match the truck’s intended size and load-capable application. It also helps to check for even seating on the rim and any obvious contact issues at full steering lock.
A heavy-duty truck places real demands on its tires, so a quick walkaround is worth doing after installation and again after the first few drives. Look for unusual rubbing, air loss, vibration, bulges, cuts, or uneven wear patterns, especially if the truck carries cargo, tows, or has been fitted with non-stock wheels.
How should tires on a 2018 RAM Trucks 2500 be maintained?
Tires on a 2018 RAM Trucks 2500 should be maintained with regular pressure checks, visual inspections, and attention to tread wear across all four positions. Because this is a heavy-duty pickup, keeping the tires properly inflated and watching for cracking, punctures, sidewall damage, or uneven wear is especially important.
Maintenance also means paying attention to how the truck is used. A RAM 2500 that tows, carries substantial loads, or spends time on rough surfaces should have its tires inspected more often, and any persistent air loss, vibration, or irregular wear should be addressed early before it leads to a larger fitment or safety problem.
