The 2015 BMW 550i GT xDrive blends grand-touring comfort, hatchback practicality, and all-wheel-drive performance in a way that sets it apart from more conventional 5 Series models. It is a modern BMW that often asks tire buyers to think carefully about wheel package and front-to-rear fitment rather than just ordering one size. This model uses radial tires in several metric sizes across 18-inch, 19-inch, and 20-inch applications, including both square and staggered setups depending on sub-model. Available choices range from blackwall performance radials to RWL and redline options in selected sizes, so the right decision comes down to matching the exact sub-model, wheel diameter, and intended look.
Which Tire Size Is Right for The 2015 BMW 550i GT xDrive
The 2015 BMW 550i GT xDrive uses five primary tire sizes, and the correct one depends on the exact sub-model and wheel package. Fitment varies across 18-inch, 19-inch, and 20-inch rims, with some versions using a square setup and others using staggered front and rear sizes. Confirming the actual sub-model and rim diameter is the first step before comparing tire series, sidewall style, or performance-oriented product differences.
245/50R18 is a metric radial size that identifies a 245-millimeter section width, a 50-series aspect ratio, radial construction, and an 18-inch rim diameter. On the 2015 BMW 550i GT xDrive, this size suits the 18-inch application and keeps the decision centered on product style rather than construction changes. Available choices in this size include Pro-Trac Street Pro III tires with either RWL or redline sidewall treatment. It is a useful fitment to evaluate when the car remains on its 18-inch wheel setup and appearance matters along with size accuracy.
245/45R19 is a metric radial size with a 245-millimeter section width, a 45-series profile, and a 19-inch rim diameter. For the 2015 BMW 550i GT xDrive, this size appears on certain 19-inch square-fitment configurations and can also serve as a front fitment reference depending on sub-model. Product choices here come from BFGoodrich and Nitto in blackwall performance-oriented series including g-Force Comp 2 AS, g-Force Phenom T/A, and NT555 G2. This size is worth close attention when the vehicle uses 19-inch wheels and the buyer wants to compare series character and rim-width compatibility.
245/40R20 is a metric radial size that combines a 245-millimeter section width with a lower 40-series profile on a 20-inch rim. On the 2015 BMW 550i GT xDrive, it serves as a front-size fitment in 20-inch applications rather than a universal size for every configuration. This size offers the broadest visible variety, with BFGoodrich, Nitto, and Pro-Trac options in blackwall, RWL, and redline sidewall styles across Street Pro III, g-Force Comp 2 AS, g-Force Phenom T/A, and NT555 G2 series. It becomes the right size to evaluate after confirming the car uses the 20-inch front wheel setup.
275/35R20 is a metric radial size with a wider 275-millimeter section width, a 35-series profile, and a 20-inch rim diameter. For the 2015 BMW 550i GT xDrive, this is a rear-size application tied to staggered 20-inch setups, so it should be selected in context with the matching front size rather than on its own. Buyers can compare BFGoodrich, Nitto, and Pro-Trac choices, including blackwall, RWL, and redline versions in several series. This size deserves careful review when maintaining the wider rear stance of a 20-inch staggered package.
275/40R19 is a metric radial size that uses a 275-millimeter section width, a 40-series profile, and a 19-inch rim diameter. On the 2015 BMW 550i GT xDrive, it functions as a rear-size fitment in certain staggered 19-inch configurations rather than a one-size solution across the range. Available blackwall products include BFGoodrich g-Force Sport Comp 2, g-Force Comp 2 AS, g-Force Phenom T/A, and the Nitto NT555 G2. It is the size to focus on when the car carries a wider 19-inch rear wheel and the goal is preserving the intended front-to-rear fitment relationship.
Sub-model fitment on the 2015 BMW 550i GT xDrive is not one-size-fits-all, because wheel diameter and front-to-rear sizing change across the range. Identifying whether the car is Base, Luxury Line, or M Sport, and whether it uses square or staggered wheels, is the key step before choosing tires.
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2015 BMW 550i GT xDrive Base
The Base model uses the 245/50R18 radial size on an 18-inch wheel setup. Tire selection here is mainly about staying with the correct 18-inch fitment while comparing available sidewall presentation and product style within that size.
The Luxury Line uses 245/45R19 as its primary radial tire size in a 19-inch application. That makes the buying decision more about comparing the available blackwall performance-oriented choices than sorting through multiple constructions.
The Luxury Line Front fitment uses 245/40R20, placing it in the 20-inch front position of a staggered setup. Selection should stay focused on front-axle size accuracy, then move to sidewall style, tire series, and wheel-width compatibility.
The Luxury Line Rear fitment uses 275/35R20, the wider rear tire for a staggered 20-inch arrangement. Matching the rear size correctly matters because tire choice needs to preserve the intended relationship with the front fitment and wheel diameter.
The M Sport sub-model uses 245/45R19 in a 19-inch radial fitment. Buyers with this setup should verify the actual wheel package on the car, then compare the blackwall tire series available in that size.
The M Sport Front fitment can use either 245/40R20 or 245/45R19, so wheel diameter must be confirmed before choosing a tire. Once the front wheel size is established, the next decision is comparing the available radial series and sidewall treatments within the correct size.
The M Sport Rear fitment can use either 275/35R20 or 275/40R19, which means the rear wheel diameter must be checked before tire selection begins. That confirmation keeps the buyer from mixing 19-inch and 20-inch rear fitments and helps preserve the intended staggered 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 2015 BMW 550i GT xDrive Tires for Sale
Available 2015 BMW 550i GT xDrive tire choices span BFGoodrich, Nitto, and Pro-Trac, with differences in tire series, blackwall versus RWL or redline sidewalls, and rim-width specifications in several 19-inch and 20-inch sizes. The product grid is most useful once the exact wheel package is confirmed.
Common questions for the 2015 BMW 550i GT xDrive usually center on identifying the correct size by sub-model, confirming 18-inch, 19-inch, or 20-inch wheel fitment, and comparing the available radial tire styles, brands, and maintenance considerations for square or staggered setups.
Tire Size & Fitment
What tire size fits a 2015 BMW 550i GT xDrive?
The 2015 BMW 550i GT xDrive uses several tire sizes rather than one universal fitment: 245/50R18, 245/45R19, 245/40R20, 275/35R20, and 275/40R19. All are radial sizes, and the right one depends on the exact sub-model and wheel package, including whether the car uses a square setup or a staggered front-and-rear arrangement.
The practical first step is confirming the actual wheel diameter on the car and whether front and rear tires are the same size. A Base model on 18-inch wheels calls for a different approach than a Luxury Line or M Sport car with 19-inch or 20-inch staggered fitment, so the tire should be matched to the current setup before comparing brands or sidewall style.
What size rim does a 2015 BMW 550i GT xDrive use?
The 2015 BMW 550i GT xDrive appears with 18-inch, 19-inch, and 20-inch rim diameters depending on sub-model and front or rear position. The 245/50R18 size uses an 18-inch rim, 245/45R19 and 275/40R19 use 19-inch rims, and 245/40R20 plus 275/35R20 use 20-inch rims.
That makes rim-diameter confirmation the most important fitment step before ordering tires. Looking only at the model name is not enough, because some versions share one front size while others use wider rear tires or move to a different wheel diameter entirely. Reading the current tire sidewall and checking the wheel package helps prevent mixing 19-inch and 20-inch applications.
Why does the 2015 BMW 550i GT xDrive have more than one tire size?
Multiple tire sizes appear on the 2015 BMW 550i GT xDrive because the model was offered with different wheel packages and with both square and staggered layouts. Some versions use one size at all four corners, while others use a narrower front tire and a wider rear tire, especially in 19-inch and 20-inch applications.
That variation means the exact sub-model name alone may not settle the question unless the wheel setup is also confirmed. A buyer should check whether the car has matching front and rear tire sizes or a staggered arrangement, then select tires that preserve the same rim diameter and front-to-rear sizing relationship already used on the vehicle.
Choosing the Right Tire
What should I consider when choosing a 245/40R20 tire for a 2015 BMW 550i GT xDrive?
Choosing a 245/40R20 tire starts with confirming that the car actually uses the 20-inch front fitment. In this size, the 2015 BMW 550i GT xDrive has options from BFGoodrich, Nitto, and Pro-Trac, with differences in series, blackwall versus RWL or redline sidewall treatment, and stated rim-width compatibility on several products.
The most useful comparison points are the intended look of the tire, whether the rest of the car uses a matching staggered setup, and whether the wheel width falls within the tire’s acceptable range. That approach helps narrow the choice between a more traditional presentation and a more modern blackwall performance look without losing sight of fitment.
What sidewall styles are available for 2015 BMW 550i GT xDrive tires?
Sidewall style depends on the tire size chosen for the 2015 BMW 550i GT xDrive. Blackwall options appear in the 19-inch and 20-inch BFGoodrich and Nitto performance sizes, while Pro-Trac Street Pro III products add RWL and redline sidewall choices in 245/50R18, 245/40R20, and 275/35R20.
That means sidewall appearance is not separate from fitment; it changes with the wheel package and size actually used on the car. Buyers looking for a cleaner late-model blackwall appearance can focus on the BFGoodrich and Nitto selections, while those wanting a more distinctive visual statement should verify that the desired RWL or redline style is offered in the exact size needed.
What brands offer tires for the 2015 BMW 550i GT xDrive?
Tire choices for the 2015 BMW 550i GT xDrive include BFGoodrich, Nitto, and Pro-Trac. Depending on size, those brands cover series such as g-Force Comp 2 AS, g-Force Phenom T/A, g-Force Sport Comp 2, NT555 G2, and Street Pro III, giving the buyer a mix of blackwall and specialty sidewall presentations.
The best way to use that brand variety is to compare within the correct size first, then look at sidewall style, rim-width suitability, and the overall character of each series. Brand choice matters less than matching the tire to the exact 18-inch, 19-inch, or 20-inch setup already on the vehicle and maintaining the intended front-to-rear combination.
Restoration & Appearance
Which tire should I choose for a period-style 2015 BMW 550i GT xDrive?
A period-style choice for a 2015 BMW 550i GT xDrive usually begins with preserving the correct original-size format already on the car, whether that means 18-inch, 19-inch, or 20-inch fitment. Within those sizes, blackwall tires give the most contemporary OEM-era appearance, while selected Pro-Trac options introduce RWL or redline styling for a more custom visual direction.
The key is deciding whether the goal is to reflect the car’s upscale grand-touring character or to add a stronger visual accent without changing the wheel package. Keeping the proper front and rear sizes in place matters more than chasing a style alone, especially on staggered setups where proportion and stance are part of the finished appearance.
How does tire construction affect the appearance of a restored 2015 BMW 550i GT xDrive?
Tire construction is straightforward on the 2015 BMW 550i GT xDrive because the primary fitments are radial throughout. That keeps the appearance question centered less on bias-ply versus radial differences and more on profile, wheel diameter, and sidewall treatment such as blackwall, RWL, or redline within the correct metric size.
Visual impact changes noticeably when a 19-inch or 20-inch staggered setup is involved, since the wider rear tire is part of the car’s overall stance. A restoration-oriented buyer should preserve the correct size relationship first, then choose a sidewall presentation that suits the intended finish of the car rather than treating all available styles as interchangeable.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2015 BMW 550i GT xDrive?
Yes, modifications can affect tire fitment on a 2015 BMW 550i GT xDrive, especially because this model already uses multiple wheel diameters and can run staggered front and rear sizes. Aftermarket wheels, suspension changes, altered ride height, or spacer changes can all influence which of the original tire sizes still makes sense on the car.
A modified car should be checked for actual wheel diameter, wheel width, and clearance at the fender, suspension, and steering positions before a tire is selected. That is particularly important on 19-inch and 20-inch setups, where mixing sizes or assuming the car still matches its original package can create unnecessary fitment problems.
What should I inspect before driving a 2015 BMW 550i GT xDrive on new tires?
Before driving a 2015 BMW 550i GT xDrive on new tires, inspect the wheel size, confirm the front and rear sizes match the intended setup, and make sure the tires seat properly on the rims. Tire pressure, valve condition, and any signs of rubbing or clearance trouble at full steering lock deserve attention right away.
A short initial road test is a smart follow-up, especially on a staggered car where one wrong size can upset the overall setup. It also helps to recheck pressure after the first drives and keep an eye on any vibration, pull, or uneven wear pattern that might point to alignment, wheel, or suspension issues rather than the tire itself.
How often should tires on a 2015 BMW 550i GT xDrive be inspected?
Tires on a 2015 BMW 550i GT xDrive should be inspected regularly, not just when tread looks low. Pressure loss, cuts, sidewall damage, uneven wear, and any developing bulges should be checked routinely, especially on cars using low-profile 19-inch or 20-inch tires where issues can become noticeable more quickly.
A consistent inspection habit matters even more when the car is driven occasionally, because age and storage conditions can affect tire condition before mileage does. Looking over the tires before longer trips, after seasonal storage, or anytime the car feels different on the road helps catch problems early and keeps the fitment working as intended.
