The 2018 Mercedes-Benz Trucks GLC63 AMG S sits in the modern high-performance luxury SUV category, where aggressive power, all-wheel-drive traction, and large-diameter wheel packages all shape the tire decision. On this model, fitment centers on a staggered radial setup, with 265-section front tires and wider 295-section rear tires, offered in either 20-inch or 21-inch diameters depending on the wheel package. That makes this page less about choosing any single universal size and more about confirming front versus rear position and wheel diameter first. Once that is settled, the focus shifts to matching the vehicle's performance character, appearance, and actual wheel setup.
Which Tire Size Is Right for The 2018 Mercedes-Benz Trucks GLC63 AMG S
The 2018 Mercedes-Benz Trucks GLC63 AMG S uses four primary tire sizes, and the correct choice depends first on wheel diameter and axle position. Front fitment uses 265-section tires, rear fitment uses wider 295-section tires, and both are offered in either 20-inch or 21-inch radial sizes. Before selecting a tire, confirm whether the vehicle is on the 20-inch or 21-inch setup and make sure front and rear sizes are not being mixed incorrectly.
265/40R21 is a metric radial size in which 265 represents nominal section width in millimeters, 40 is the aspect ratio, R indicates radial construction, and 21 identifies the wheel diameter. On the 2018 Mercedes-Benz Trucks GLC63 AMG S, this size belongs to the front position on the 21-inch setup rather than serving as a universal fitment for all four corners. Its role is to maintain the proper front side of the staggered arrangement. Buyers should confirm axle position, wheel diameter, and the vehicle's current wheel package before choosing this size.
265/45R20 is a metric radial tire size with a 265-millimeter nominal section width, a 45-series profile, and a 20-inch rim diameter. For the 2018 Mercedes-Benz Trucks GLC63 AMG S, it serves as the front tire size on the 20-inch staggered setup, paired with a wider rear tire rather than used at all four corners. The slightly different profile is tied to the smaller wheel diameter, not to a change in vehicle type or trim family. This is the size to evaluate when the GLC63 AMG S has 20-inch front wheels already in place.
295/35R21 is a metric radial size where 295 is the nominal width in millimeters, 35 is the aspect ratio, and 21 is the rim diameter in inches. On the 2018 Mercedes-Benz Trucks GLC63 AMG S, this is the rear size used with the 21-inch wheel package, reflecting the model's wider rear fitment in a staggered arrangement. Its job is not interchangeable with the front size, even though both belong to the same vehicle. Choose this size only after confirming that the rear wheels are 21-inch and that the vehicle still carries the matching 21-inch front and rear combination.
295/40R20 is a metric radial tire with a 295-millimeter nominal section width, a 40-series profile, and a 20-inch rim diameter. It is the rear tire size for the 20-inch staggered setup on the 2018 Mercedes-Benz Trucks GLC63 AMG S, working with a narrower 265/45R20 front tire rather than matching the front size. Available product choice in this size includes the Nitto NT555 G2 in a Blackwall performance-oriented radial design. This size is the right one to review when replacing the rear tires on a GLC63 AMG S that remains on its 20-inch wheel package.
2018 Mercedes-Benz Trucks GLC63 AMG S Sub-Model Tires
Fitment on the 2018 Mercedes-Benz Trucks GLC63 AMG S is straightforward once the axle position is identified, because the front and rear use different tire sizes. Checking that distinction matters just as much as confirming whether the vehicle is on the 20-inch or 21-inch wheel setup.
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2018 Mercedes-Benz Trucks GLC63 AMG S 4Matic Front
The 2018 Mercedes-Benz Trucks GLC63 AMG S 4Matic Front uses a 265-section radial tire, with fitment tied to either a 20-inch or 21-inch wheel package. Tire selection here starts with confirming wheel diameter, then matching the front position rather than choosing by overall vehicle name alone.
The 2018 Mercedes-Benz Trucks GLC63 AMG S 4Matic Rear uses the wider 295-section radial tire, again split between 20-inch and 21-inch wheel packages. That wider rear fitment means replacement tires should be chosen specifically for the rear axle and checked against the current wheel setup.
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 Mercedes-Benz Trucks GLC63 AMG S Tires for Sale
Available product choice currently centers on the 295/40R20 rear size, with a Nitto Blackwall radial option in the NT555 G2 series. For this GLC63 AMG S, the most important comparisons remain rear size, 20-inch wheel compatibility, and maintaining the staggered front-to-rear setup.
These FAQs focus on the staggered tire fitment used on the 2018 Mercedes-Benz Trucks GLC63 AMG S, including front versus rear sizing, 20-inch and 21-inch wheel setups, product selection, and the checks that matter before road use.
Tire Size & Fitment
What tire size fits a 2018 Mercedes-Benz Trucks GLC63 AMG S?
The 2018 Mercedes-Benz Trucks GLC63 AMG S uses a staggered radial tire setup rather than one universal size. Front fitment is either 265/45R20 or 265/40R21, while rear fitment is either 295/40R20 or 295/35R21, depending on whether the vehicle is equipped with 20-inch or 21-inch wheels.
That means the first step is confirming both axle position and wheel diameter before replacing any tire. A front size should not be selected for the rear, and a 20-inch tire should not be chosen for a 21-inch wheel. If the vehicle has been modified with aftermarket wheels, verify the actual sizes on the vehicle before ordering replacements.
What size rim does a 2018 Mercedes-Benz Trucks GLC63 AMG S use?
The 2018 Mercedes-Benz Trucks GLC63 AMG S uses either 20-inch or 21-inch rims, depending on the tire and wheel package on the vehicle. The 265/45R20 and 295/40R20 sizes mount on 20-inch rims, while the 265/40R21 and 295/35R21 sizes mount on 21-inch rims.
Rim diameter is the key fitment check because this model uses two different wheel diameters across its supported tire sizes. A tire's final number must match the wheel exactly, so a 20-inch tire cannot be used on a 21-inch wheel or the reverse. Checking the sidewall and wheel before purchase helps avoid front-to-rear or diameter mismatches.
Why does the 2018 Mercedes-Benz Trucks GLC63 AMG S have more than one tire size?
The 2018 Mercedes-Benz Trucks GLC63 AMG S has more than one tire size because it uses a staggered setup and was offered with different wheel diameters. The front axle uses a narrower 265-section tire, the rear uses a wider 295-section tire, and each axle can be paired with either a 20-inch or 21-inch wheel package.
That combination creates four valid primary sizes, but not all four belong on the vehicle at the same time. The correct pair depends on the wheel package already on the SUV. Selecting replacements becomes much simpler once the current wheels are confirmed, since that immediately narrows the choice to one front size and one rear size.
Choosing the Right Tire
What should I consider when choosing a tire for a 2018 Mercedes-Benz Trucks GLC63 AMG S?
Start with the fundamentals: front versus rear position, 20-inch versus 21-inch wheel diameter, and the exact size already on the vehicle. The 2018 Mercedes-Benz Trucks GLC63 AMG S uses staggered radial fitment, so the right choice is not simply any tire that looks close in width or profile.
After size is confirmed, compare tire character and product details that matter to your setup, such as sidewall style, tire series, and other published specifications. A performance-oriented SUV like this benefits from keeping the staggered arrangement intact. Vehicles with aftermarket wheels or suspension changes should have clearance and wheel compatibility checked before moving ahead.
What sidewall styles are available for 2018 Mercedes-Benz Trucks GLC63 AMG S tires?
Current product choice for the 2018 Mercedes-Benz Trucks GLC63 AMG S includes a Blackwall sidewall style in the 295/40R20 rear size. That gives the tire a clean modern appearance that suits a contemporary high-performance SUV without introducing vintage-style sidewall treatments.
Sidewall style affects appearance more than fitment, so it should be chosen after the correct size and wheel diameter are confirmed. On a vehicle with a staggered setup, visual consistency also matters from front to rear. If matching appearance across all four corners is important, check that the front and rear tires you choose follow the same general presentation.
What brands offer tires for the 2018 Mercedes-Benz Trucks GLC63 AMG S?
Available product coverage for the 2018 Mercedes-Benz Trucks GLC63 AMG S currently includes Nitto in the 295/40R20 rear size. The tire offered there is part of the NT555 G2 series and uses radial construction with a Blackwall sidewall treatment.
Brand should be part of a broader selection process rather than the first filter. Correct front or rear fitment, wheel diameter, and the intended use of the SUV matter more at the start. Once those points are settled, comparing series design, sidewall style, and other tire specifications will usually tell you more than a brand name alone.
Restoration & Appearance
How does tire construction affect the appearance of a 2018 Mercedes-Benz Trucks GLC63 AMG S?
On the 2018 Mercedes-Benz Trucks GLC63 AMG S, tire construction is straightforward because the vehicle uses radial sizes across its supported fitments. The visual effect comes less from a bias-ply-versus-radial decision and more from choosing the proper staggered proportions, correct wheel diameter, and a sidewall treatment that suits the vehicle's modern performance character.
Appearance can change noticeably if the wrong front or rear size is installed, even if the tire technically matches the wheel diameter. Keeping the intended 265 front and 295 rear relationship preserves the stance this model was designed around. If visual balance matters, check both axle sizing and sidewall style before replacing only part of the set.
Does correct tire fitment matter for a 2018 Mercedes-Benz Trucks GLC63 AMG S restoration or preservation project?
Correct tire fitment matters because the 2018 Mercedes-Benz Trucks GLC63 AMG S relies on a staggered arrangement and large-diameter wheel package for both its look and its intended setup. Preserving the proper front and rear relationship helps maintain the vehicle's original visual proportions far better than simply choosing any modern tire that fits the wheel.
For a preservation-minded owner, the key details are axle position, wheel diameter, and sidewall presentation. A mismatched front-to-rear combination can change the stance quickly. If exact appearance matters, inspect the current wheel and tire package carefully before replacement so the new tires support the same overall look rather than altering it unintentionally.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2018 Mercedes-Benz Trucks GLC63 AMG S?
Yes, modifications can affect tire fitment on a 2018 Mercedes-Benz Trucks GLC63 AMG S, especially because the vehicle already uses a staggered setup with either 20-inch or 21-inch wheels. Changes such as aftermarket wheels, altered wheel widths, suspension lowering, or body modifications can all influence clearance and tire choice.
Even when a tire matches the printed size, the actual wheel and vehicle setup still need to be checked. Offset, suspension travel, and steering clearance all matter once the factory configuration has been changed. A modified vehicle should be measured and inspected carefully before replacement tires are selected, particularly when replacing only one axle.
What should I inspect before driving a 2018 Mercedes-Benz Trucks GLC63 AMG S on new tires?
Before driving a 2018 Mercedes-Benz Trucks GLC63 AMG S on new tires, confirm that the front and rear sizes are installed in the correct positions and that wheel diameter matches the tire size. It is also wise to inspect inflation pressure, valve stems, tread condition, and the tire sidewalls for any shipping or mounting damage.
A short visual and hands-on check can prevent common setup issues from turning into road problems. Look for adequate clearance at the fenders and suspension, especially if the SUV has aftermarket wheels. Rechecking pressure after the first drives is also smart, since proper inflation supports even wear and helps the staggered setup behave as intended.
What should I check before a longer drive in a 2018 Mercedes-Benz Trucks GLC63 AMG S?
Before a longer drive, check that the 2018 Mercedes-Benz Trucks GLC63 AMG S has the correct front and rear tire sizes for its current 20-inch or 21-inch wheel package, and inspect the tires for cuts, bulges, cracking, uneven wear, or signs of air loss. Pressure should also be verified while the tires are cold.
Longer trips place more demand on the entire tire and wheel package, so basic condition checks matter even on newer-looking tires. Pay attention to any vibration, pulling, or rubbing from previous drives, since those symptoms can point to a fitment or wear issue. Collector or low-use vehicles deserve extra attention because age can affect tire condition before tread wears out.
