The 2018 Mercedes-Benz S450 sits in the modern full-size luxury sedan tradition, blending long-wheelbase comfort, quiet high-speed road manners, and the kind of wheel-and-tire presence that strongly shapes the car’s stance. Tire fitment on this model is entirely radial, but it is not a one-size-fits-all setup. Depending on configuration, the S450 uses either a square 245/50R18 arrangement or staggered 19-inch and 20-inch front-and-rear combinations. That creates meaningful choices in sidewall style, tire series, and brand, especially on the staggered setups. The right selection starts with confirming whether the car remains on 18-inch wheels or uses the 19-inch or 20-inch front-and-rear package.
Which Tire Size Is Right for The 2018 Mercedes-Benz S450
The 2018 Mercedes-Benz S450 uses five tire sizes across three rim diameters, and the correct choice depends on whether the car has a square 18-inch setup or a staggered 19-inch or 20-inch front-and-rear arrangement. Before choosing a tire, confirm the exact sub-model position and wheel diameter, because the front and rear sizes differ on the staggered versions.
245/50R18 is a metric radial size in which 245 identifies the section width in millimeters, 50 is the aspect ratio, and 18 is the wheel diameter in inches. On the 2018 Mercedes-Benz S450, this size serves the square 18-inch fitment rather than a staggered front-and-rear package. Available choices include Pro-Trac Street Pro III tires with either RWL or Redline sidewall styling. This size is the right place to start when the car remains on its 18-inch wheel setup and appearance matters as much as basic fitment.
245/40R20 is a metric radial size with a 245-millimeter nominal section width, a 40-series profile, and a 20-inch rim diameter. On the 2018 Mercedes-Benz S450, it is used in the front position of the staggered 20-inch arrangement, so it should be matched to the correct rear size rather than treated as a stand-alone fitment. Choices in this size include BFGoodrich, Nitto, and Pro-Trac, with Blackwall, RWL, and Redline sidewall treatments depending on the tire series. It is the correct front size to evaluate only after confirming that the car is on the 20-inch staggered package.
245/45R19 is a metric radial size where 245 gives the nominal section width in millimeters, 45 is the aspect ratio, and 19 indicates a 19-inch wheel. On the 2018 Mercedes-Benz S450, this size is used at the front of the staggered 19-inch setup and should be paired with the matching rear size for a balanced configuration. Available options come from BFGoodrich and Nitto, primarily in Blackwall form across g-Force and NT555 G2 series choices. This is the size to compare when the car carries 19-inch front wheels and the goal is a proper front staggered fitment.
275/35R20 is a metric radial size with a wider 275-millimeter section width, a 35-series profile, and a 20-inch rim diameter. On the 2018 Mercedes-Benz S450, it serves the rear position of the staggered 20-inch arrangement, complementing the narrower 245/40R20 front tire. Product choices include BFGoodrich, Nitto, and Pro-Trac, with Blackwall, RWL, and Redline sidewall treatments depending on the tire line. This size should be evaluated as part of the full 20-inch staggered package, with attention to rear wheel width and overall front-to-rear setup.
275/40R19 is a metric radial size that combines a 275-millimeter nominal section width with a 40-series profile on a 19-inch wheel. On the 2018 Mercedes-Benz S450, this is the rear tire for the staggered 19-inch setup, paired with the narrower 245/45R19 front size. BFGoodrich and Nitto offer the main choices here, including several g-Force series options and the NT555 G2, generally with Blackwall styling. This size belongs in a rear-specific decision process, so the key is confirming that the car uses the 19-inch staggered wheel package before comparing tires.
Sub-model fitment on the 2018 Mercedes-Benz S450 is split between square and staggered arrangements. Checking whether the car is a standard full-set fitment or a front-and-rear position fitment matters first, because wheel diameter and tire size both change across these configurations.
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2018 Mercedes-Benz S450 4Matic
The 2018 Mercedes-Benz S450 4Matic uses the square 245/50R18 radial fitment rather than a staggered front-and-rear setup. Tire selection centers on staying with the 18-inch configuration and choosing the sidewall presentation that best matches the car’s intended look.
The 2018 Mercedes-Benz S450 4Matic Front position uses either 245/40R20 or 245/45R19, depending on which staggered wheel package is on the car. The main step here is confirming wheel diameter first, then selecting a front tire that matches the corresponding rear setup.
The 2018 Mercedes-Benz S450 4Matic Rear position uses either 275/35R20 or 275/40R19, matching the car’s staggered wheel package. Rear tire choice should follow wheel-diameter confirmation and should be considered alongside the front size already on the vehicle.
The 2018 Mercedes-Benz S450 Base uses the same 245/50R18 radial tire size as the square-fitment 4Matic configuration. That makes the decision more about tire style and appearance than sorting through multiple primary sizes for the whole vehicle.
The 2018 Mercedes-Benz S450 Base Front position uses either 245/40R20 or 245/45R19 on staggered setups. Selecting the right tire starts with confirming whether the front wheel is 19 or 20 inches, then matching it to the rear package already in place.
The 2018 Mercedes-Benz S450 Base Rear position uses either 275/35R20 or 275/40R19 in a staggered arrangement. Choosing correctly means verifying the rear wheel diameter and making sure the rear tire remains properly paired with the front size on the car.
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 S450 Tires for Sale
Available 2018 Mercedes-Benz S450 tires vary by size, brand, tire series, and sidewall treatment. Depending on the fitment, buyers can compare BFGoodrich, Nitto, and Pro-Trac options across Blackwall, RWL, and Redline styles, with the most visual variety appearing in the 18-inch and 20-inch sizes.
Owners of a 2018 Mercedes-Benz S450 usually need to sort out wheel diameter, front-versus-rear sizing, and tire style before making a selection. These FAQs focus on exact fitment, available radial choices, appearance differences, and the checks that matter before road use.
Tire Size & Fitment
What tire size fits a 2018 Mercedes-Benz S450?
The 2018 Mercedes-Benz S450 uses several radial tire sizes: 245/50R18, 245/45R19, 275/40R19, 245/40R20, and 275/35R20. The 18-inch setup uses 245/50R18, while the 19-inch and 20-inch configurations use staggered front-and-rear sizes with a narrower front tire and a wider rear tire.
The practical step is confirming which wheel package is actually on the car before choosing tires. A square 18-inch setup is selected differently from a staggered 19-inch or 20-inch arrangement, and the front and rear sizes should be matched to the same wheel diameter and overall package.
What size rim does a 2018 Mercedes-Benz S450 use?
A 2018 Mercedes-Benz S450 can use 18-inch, 19-inch, or 20-inch rims depending on configuration. The square fitment uses an 18-inch wheel with 245/50R18 tires, while the staggered arrangements pair either 19-inch front and rear sizes or 20-inch front and rear sizes.
Wheel diameter is the first thing to verify because the S450 does not use one universal rim size across all setups. Once diameter is confirmed, check whether the car has the same size tire at all four corners or uses a staggered package with different front and rear widths.
Why does the 2018 Mercedes-Benz S450 have more than one tire size?
The 2018 Mercedes-Benz S450 has more than one tire size because it was fitted in both square and staggered wheel-and-tire arrangements. Some versions use 245/50R18 at all four corners, while others use 19-inch or 20-inch front-and-rear combinations with 245-width front tires and 275-width rear tires.
That means tire selection starts with identifying the exact wheel setup rather than searching for one universal size. Looking at the tire sidewall and confirming front and rear measurements separately helps prevent mixing 19-inch and 20-inch components or ordering only one side of a staggered package.
Choosing the Right Tire
What should I consider when choosing a tire for a 2018 Mercedes-Benz S450?
Start with the correct size and wheel configuration, because the 2018 Mercedes-Benz S450 may use a square 245/50R18 setup or staggered 19-inch or 20-inch front-and-rear sizes. From there, compare tire series, sidewall presentation, and any product details such as rim-width guidance or load figures where they are stated.
The best choice depends on how the car is used and how you want it to look. A blackwall performance-style radial gives a different visual impression than an RWL or Redline tire, and staggered setups need both axle positions considered together rather than shopping for one corner in isolation.
What sidewall styles are available for 2018 Mercedes-Benz S450 tires?
Sidewall style depends on the tire size. The 18-inch 245/50R18 and the 20-inch staggered sizes include RWL and Redline choices from Pro-Trac, while several 19-inch and 20-inch performance-oriented options from BFGoodrich and Nitto use Blackwall styling.
That makes sidewall treatment part of the buying decision, not just a cosmetic afterthought. If the goal is a cleaner modern look, Blackwall choices fit that direction, while RWL or Redline options create a more customized appearance that stands out more strongly against the S450’s wheel-and-tire package.
What brands offer tires for the 2018 Mercedes-Benz S450?
Tires for the 2018 Mercedes-Benz S450 are available from BFGoodrich, Nitto, and Pro-Trac, depending on the size. BFGoodrich appears across several g-Force series, Nitto offers NT555 G2 options, and Pro-Trac covers Street Pro III fitments with visual sidewall variations in selected sizes.
Brand choice should come after fitment is settled, since not every brand appears in every S450 size. Once the correct 18-inch, 19-inch, or 20-inch setup is confirmed, compare the available lines in that exact size for sidewall style, rim-width compatibility where stated, and the overall presentation you want.
Restoration & Appearance
Which tire should I choose for a period-style 2018 Mercedes-Benz S450?
A period-style approach on a 2018 Mercedes-Benz S450 starts with keeping the correct wheel diameter and front-to-rear sizing arrangement already on the car. From there, the visual character comes from the tire line and sidewall treatment, with Blackwall, RWL, and Redline choices available in certain sizes.
Because this is a modern luxury sedan, appearance usually leans more toward preserving the intended stance than recreating an antique tire look. Matching the original wheel setup, especially on staggered 19-inch or 20-inch packages, does more for the car’s overall presence than chasing a style that ignores its actual fitment.
How does tire construction affect the appearance of a restored 2018 Mercedes-Benz S450?
Construction is straightforward on the 2018 Mercedes-Benz S450 because the applicable fitments are radial. The appearance difference comes less from bias-ply versus radial choice and more from sidewall styling, tire series, and whether the car sits on the square 18-inch setup or the wider staggered 19-inch or 20-inch package.
That means visual planning should focus on maintaining the correct size relationship front to rear and selecting a sidewall treatment that suits the car’s finish and wheels. Even small styling changes can alter the overall presentation, especially when a wide rear tire and lower-profile front tire are part of the package.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2018 Mercedes-Benz S450?
Yes, modifications can affect tire fitment on a 2018 Mercedes-Benz S450. If the car has aftermarket wheels, suspension changes, altered ride height, or body modifications, the original relationship between tire width, wheel diameter, and available clearance may no longer match the standard 18-inch, 19-inch, or 20-inch setups.
That is especially important on staggered fitments, where both axle position and wheel diameter matter. Checking front and rear wheel width, confirming sidewall clearance at steering lock, and measuring space around the fender and suspension helps prevent problems when replacing tires on a modified car.
What should I inspect before driving a 2018 Mercedes-Benz S450 on new tires?
Before road use, inspect the new tires for correct size, proper front-versus-rear placement, and consistent mounting on the intended wheel diameter. Also look over the wheels themselves for damage, verify inflation, and make sure valve stems, balancing, and general installation quality are in order.
A short clearance check is worthwhile before normal driving, particularly on staggered 19-inch or 20-inch setups. Turn the steering from lock to lock, watch for contact points, and confirm that the tires sit properly within the fenders and away from suspension components once the car is on the ground.
How should tires on a 2018 Mercedes-Benz S450 be maintained?
Tires on a 2018 Mercedes-Benz S450 should be maintained with regular pressure checks, visual inspections, and close attention to tread condition and sidewall health. Watch for cuts, bulges, cracking, uneven wear, and slow air loss, and inspect both front and rear tires because staggered setups place different sizes at each axle.
Cars that are driven less often still need routine checks, since age and storage conditions matter as much as mileage. Keeping the vehicle away from prolonged sunlight, excess heat, and ozone sources helps preserve the tires, and any unusual wear pattern should prompt a closer look at alignment and wheel condition.
