The 2008 Mercedes-Benz S550 sits in the modern flagship luxury-sedan tradition, blending substantial road presence with the quiet, high-speed touring character expected of an S-Class. Tire choice on this car is closely tied to configuration, because the S550 uses radial fitments in three sizes: 255/45R18, 255/40R19, and 275/40R19. Standard setups stay with 18-inch fitment, while Sport Package cars move to 19-inch sizes, including a staggered front-and-rear arrangement on some versions. That makes this page less about vintage construction choices and more about confirming the exact sub-model, wheel diameter, and whether the goal is original-style sizing, sport appearance, or dependable road use.
Which Tire Size Is Right for The 2008 Mercedes-Benz S550
Three tire sizes apply to the 2008 Mercedes-Benz S550, and the right one depends on the exact sub-model and wheel setup. The standard fitment uses 255/45R18 on an 18-inch rim, while Sport Package versions use 19-inch fitments, including a staggered arrangement with 255/40R19 in front and 275/40R19 in the rear. Confirming both the sub-model and the wheel diameter should come first before comparing brands, sidewall styles, or tire series.
A 255/45R18 tire uses a 255-millimeter nominal section width, a 45-series aspect ratio, radial construction, and an 18-inch rim diameter. On the 2008 Mercedes-Benz S550, this is the standard radial fitment used on non-Sport configurations such as the Base and 4Matic models. Available choices include BFGoodrich, Nitto, and Pro-Trac options, with Blackwall, raised white letter, and Redline sidewall treatments depending on the tire series. This size is the right starting point when the car remains on its original 18-inch wheel setup and the goal is to balance proper fitment with the preferred visual style.
Fit(s): 4Matic w/Sport Pkg. and w/Sport Pkg. Front
Construction: Radial|Rim: 19 in
A 255/40R19 tire keeps the same 255-millimeter nominal width but uses a shorter 40-series profile on a 19-inch rim. On the 2008 Mercedes-Benz S550, this size belongs to Sport Package front fitment and to the 4Matic w/Sport Pkg. configuration, so it should not be assumed across every S550. Product choices include BFGoodrich and Pro-Trac tires in several series, mostly Blackwall but also with raised white letter and Redline options. This size matters most when confirming a 19-inch front or all-around sport setup rather than a standard 18-inch wheel package.
A 275/40R19 tire is wider than the 255 sizes, using a 275-millimeter nominal section width with a 40-series profile on a 19-inch rim. On the 2008 Mercedes-Benz S550, it serves as the rear tire on the w/Sport Pkg. Rear application, making it part of a staggered sport setup rather than a universal fitment. Available options include BFGoodrich and Nitto Blackwall radials across several performance-oriented series. This is the size to evaluate when the car uses wider rear 19-inch wheels and the rear fitment needs to match the front sport configuration properly.
Sub-model fitment matters on the 2008 Mercedes-Benz S550 because wheel size and tire size change between standard and Sport Package configurations. A quick check of the exact sub-model helps separate the 18-inch setup from the 19-inch sport and staggered applications before choosing a tire.
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2008 Mercedes-Benz S550 4Matic
The 2008 Mercedes-Benz S550 4Matic uses the standard 255/45R18 radial fitment rather than the lower-profile sport sizes. Tire selection here centers on choosing the preferred brand, series, and sidewall treatment while staying with the correct 18-inch wheel setup.
The 2008 Mercedes-Benz S550 4Matic w/Sport Pkg. uses 255/40R19, moving to a shorter-profile radial on a 19-inch rim. That makes wheel confirmation especially important before purchase, followed by comparison of the available Blackwall, RWL, or Redline product choices in this size.
The 2008 Mercedes-Benz S550 Base uses the same 255/45R18 radial size as the standard non-sport setup. Owners can focus on matching the correct 18-inch fitment first, then sorting through differences in brand, tire series, and sidewall appearance.
The 2008 Mercedes-Benz S550 w/Sport Pkg. Front uses 255/40R19 as the front portion of a sport-oriented 19-inch arrangement. Tire selection should keep the front size distinct from the wider rear fitment so the staggered setup remains properly matched.
The 2008 Mercedes-Benz S550 w/Sport Pkg. Rear uses 275/40R19, the wider rear tire in the staggered Sport Package arrangement. Choosing in this position means confirming the rear wheel setup and selecting a tire that matches the intended front-and-rear sport sizing strategy.
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 2008 Mercedes-Benz S550 Tires for Sale
Available 2008 Mercedes-Benz S550 tires cover the three correct radial sizes with choices from BFGoodrich, Nitto, and Pro-Trac. Depending on size, buyers can compare Blackwall, raised white letter, and Redline sidewalls across series such as g-Force Sport Comp 2, g-Force Comp 2 AS, g-Force Phenom T/A, Street Pro III, and NT555 G2.
These FAQs focus on the exact tire sizes used on the 2008 Mercedes-Benz S550, how fitment changes between standard and Sport Package versions, and what to compare when choosing tires for appearance, wheel compatibility, and road use.
Tire Size & Fitment
What tire size fits a 2008 Mercedes-Benz S550?
The 2008 Mercedes-Benz S550 uses three tire sizes depending on configuration: 255/45R18, 255/40R19, and 275/40R19. Standard Base and 4Matic versions use 255/45R18, while Sport Package applications move to 19-inch fitment, with 255/40R19 used in front and 275/40R19 used in the rear on staggered setups.
That means the first step is identifying whether the car is a standard model, a Sport Package model, or a staggered front-and-rear sport setup. Checking the existing wheel diameter and confirming whether the car has matched or staggered wheels will help avoid ordering the right size for the wrong position.
What size rim does a 2008 Mercedes-Benz S550 use?
A 2008 Mercedes-Benz S550 uses either an 18-inch or 19-inch rim, depending on the sub-model and package. The 255/45R18 fitment uses an 18-inch rim, while both 255/40R19 and 275/40R19 use 19-inch rims on Sport Package applications.
Rim diameter should be confirmed before anything else because the S550 does not use one universal wheel size across all versions. After diameter is verified, wheel width and front-versus-rear placement become the next checks, especially on cars with a sport package or any wheel changes made after the car left its original setup.
Why does the 2008 Mercedes-Benz S550 have more than one tire size?
The 2008 Mercedes-Benz S550 has more than one tire size because fitment changes with the vehicle configuration. Standard Base and 4Matic models use 255/45R18, while Sport Package versions move to 19-inch tires, and the staggered sport arrangement uses 255/40R19 in front with 275/40R19 in the rear.
This is not a case of interchangeable sizing across the whole model line. Tire choice depends on whether the car has standard wheels or the Sport Package setup, so it helps to check the sub-model name, read the sidewall on the current tires, and confirm whether the front and rear wheels are the same size or not.
Choosing the Right Tire
What should I consider when choosing a tire for a 2008 Mercedes-Benz S550?
Start with the correct size for the exact S550 configuration, because this car uses 255/45R18, 255/40R19, or 275/40R19 depending on wheel package and axle position. From there, compare tire construction, brand, series, sidewall style, and wheel-width compatibility where those details are available.
A standard 18-inch setup calls for a different decision than a 19-inch Sport Package arrangement, and a staggered setup adds another layer because the rear tire is wider. It also helps to think about how the car is used, whether the priority is a restrained Blackwall appearance or a more distinctive RWL or Redline presentation.
What sidewall styles are available for 2008 Mercedes-Benz S550 tires?
Sidewall style depends on the size selected. Blackwall choices are available across all three S550 tire sizes, while raised white letter and Redline options appear in 255/45R18 and 255/40R19 through Pro-Trac Street Pro III offerings.
That gives the 18-inch and front 19-inch fitments more visual variety than the 275/40R19 rear size, which stays in a Blackwall presentation. Buyers who want a cleaner late-model luxury look often stay with Blackwall, while those after a more customized or sport-themed appearance may want to compare RWL and Redline options carefully.
What brands offer tires for the 2008 Mercedes-Benz S550?
Tires for the 2008 Mercedes-Benz S550 are available from BFGoodrich, Nitto, and Pro-Trac, depending on the size. BFGoodrich appears across all three fitments, Nitto is available in 255/45R18 and 275/40R19, and Pro-Trac covers 255/45R18 and 255/40R19.
Brand alone should not decide the purchase, because the real comparison also includes series, sidewall style, and wheel-width fit. It helps to look at the complete tire description for the exact size on the car, especially if the goal is to match a standard luxury-sedan setup or maintain the look of a Sport Package wheel arrangement.
Restoration & Appearance
Which tire should I choose for a period-style 2008 Mercedes-Benz S550?
A period-style 2008 Mercedes-Benz S550 starts with keeping the correct original-size relationship for the car's configuration. That means 255/45R18 on standard Base and 4Matic models, or the correct 19-inch sizing on Sport Package versions, rather than choosing a tire solely by appearance.
Once the right size is established, the look can be tailored through the available product lines and sidewall treatments. Blackwall keeps the restrained luxury-sedan presentation most buyers associate with an S-Class, while RWL or Redline options create a more customized visual statement that changes the character of the car without changing its basic fitment.
How does tire construction affect the appearance of a restored 2008 Mercedes-Benz S550?
On a 2008 Mercedes-Benz S550, construction is straightforward because the fitments are radial rather than vintage bias-ply. Appearance is influenced less by construction type and more by the overall size, profile, wheel diameter, and sidewall treatment chosen for the exact 18-inch or 19-inch setup.
That makes it important to preserve the intended stance of the car by keeping the proper standard or Sport Package sizing arrangement. A Blackwall tire usually maintains the most understated look, while raised white letter or Redline options add visual emphasis that may suit a personalized build more than a stock-looking presentation.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2008 Mercedes-Benz S550?
Yes, modifications can affect tire fitment on a 2008 Mercedes-Benz S550. Changes such as aftermarket wheels, altered wheel widths, different offsets, suspension lowering, or body modifications can change how 255/45R18, 255/40R19, or 275/40R19 tires sit in the car and whether clearance remains adequate.
A car that still uses its original wheel package is much easier to match correctly than one that has been changed over time. Measuring the actual wheel diameter and width, then checking front and rear tire clearance at full steering lock and suspension travel, is a smart step before replacing tires on a modified S550.
What should I inspect before driving a 2008 Mercedes-Benz S550 on new tires?
Before driving a 2008 Mercedes-Benz S550 on new tires, inspect wheel condition, valve stems, and the actual tire size installed at each corner. The tires should be checked for proper inflation, secure mounting, and enough clearance around the fenders, suspension, and steering components, especially on 19-inch Sport Package or staggered setups.
It also helps to verify that the front and rear positions are not accidentally mixed on sport cars using different sizes. After a short initial drive, recheck air pressure and look for any signs of rubbing or uneven seating, since those early checks can reveal wheel or fitment issues before longer road use.
How should tires on a 2008 Mercedes-Benz S550 be maintained?
Tires on a 2008 Mercedes-Benz S550 should be maintained with regular pressure checks, visual inspections, and routine attention to tread and sidewall condition. Even on a newer collector-oriented luxury sedan, low annual mileage can hide age-related concerns such as cracking, flat spotting, or gradual air loss.
Storage conditions matter too, especially if the car spends long periods parked. Keeping the S550 away from prolonged sun, excess heat, moisture, and ozone-producing equipment helps protect the tires, while periodic inspection of alignment wear and suspension condition helps the correct-size tires deliver the road manners expected from this chassis.
