2015 Infiniti Tire Fitment Guide

2015 Infiniti vehicles use eight sizes across five models: 225/55R17 for Q40 and some Q50 applications; 245/40R19 and 265/35R19 for Q50; 225/45R19, 225/50R18, 245/40R19, and 245/45R18 for Q60; and 245/40R20 plus 245/50R18 for Q70 and Q70L. These are all radial sizes, but they do not share one universal wheel diameter across the full lineup.

Rim width support varies by size where published. 225/55R17 fits 6.0 to 9.0 inches depending on product, 245/40R19 fits 8.0 to 9.5, 225/45R19 fits 7.0 to 8.5, 225/50R18 fits 6.0 to 8.0, 245/45R18 fits 7.5 to 9.0, and 245/40R20 fits 8.0 to 9.5. The first thing to confirm is the exact model and wheel diameter already on the car, then compare the tire’s approved rim-width range against the actual wheel before ordering.

On a 2015 Infiniti, 225/55R17 is a metric radial size. The 225 is the nominal section width in millimeters, 55 is the aspect ratio, meaning the sidewall height is 55 percent of the section width, R identifies radial construction, and 17 is the wheel diameter in inches. That size appears on the Q40 and on certain Q50 applications.

Understanding the code helps separate it from Infiniti’s lower-profile 18-, 19-, and 20-inch fitments. A 225/55R17 tire has more sidewall than the 40- or 35-series alternatives elsewhere in the lineup, so it belongs only on the proper 17-inch wheel. When replacing tires on a Q40 or Q50, match the full size code rather than just the width, because the aspect ratio and rim diameter are what keep overall fitment in the intended range.

No, 2015 Infiniti models use several different tire sizes depending on model and wheel package. The Q40 uses 225/55R17, the Q50 spans 225/55R17, 245/40R19, and 265/35R19, the Q60 uses four different 18- and 19-inch sizes, and the Q70 and Q70L use either 245/50R18 or 245/40R20. Even where two models share a size, that does not make it universal across the entire make.

That means year and make alone are not enough for accurate tire selection on 2015 Infiniti. Buyers should confirm the exact model, then verify whether the car has its original wheel package or a different diameter wheel from another trim or owner change. Once the wheel diameter is known, the correct size range becomes much easier to narrow down, especially on Q50, Q60, Q70, and Q70L applications that could have more than one factory-style fitment.

Most 2015 Infiniti sizes are available in Blackwall form, which aligns with the contemporary luxury and sport-sedan look these cars carried when new. A few sizes add alternate visual treatments: 225/55R17 is also available as a Wide Whitewall, 245/40R20 is available in RWL, and 245/50R18 is available in both RWL and Redline. Those appearance choices are far more custom in character than original-equipment styled for a 2015 Infiniti.

For an owner who wants a factory-like appearance, Blackwall is the natural place to start on any Q40, Q50, Q60, Q70, or Q70L. Whitewall, redline, and raised white letter sidewalls can work when the goal is a personalized build, but they change the visual tone of the car substantially. The smartest approach is to choose the correct size first, then decide whether the sidewall should stay modern and understated or become a deliberate styling statement.

2015 Infiniti tire coverage comes from BFGoodrich, Nitto, and Pro-Trac, depending on the size. BFGoodrich appears across most of the range, including 225/55R17, 245/40R19, 225/45R19, 225/50R18, 245/45R18, and 245/40R20. Nitto joins BFGoodrich in 265/35R19, 245/45R18, and 245/40R20, while Pro-Trac covers 245/40R20 and 245/50R18.

Brand choice on 2015 Infiniti often tracks with the exact size and the appearance the owner wants. Some sizes focus on contemporary blackwall performance radials, while others add more visual sidewall variety through Pro-Trac offerings. If you are comparing options, start by matching the exact factory-style size on the car, then decide whether your priority is a straightforward modern radial look or a more customized sidewall treatment within that same fitment.

For a 2015 Infiniti using 245/45R18, BFGoodrich offers multiple choices in that size, including W-rated and Y-rated versions, while Nitto offers the NT555 G2 in 245/45ZR18 XL 100W. The shared rim-width range centers on 7.5 to 9.0 inches, and load figures reach 1,764 pounds at 50 psi on both the Nitto NT555 G2 and the BFGoodrich g-Force Phenom T/A. All of them use a Blackwall sidewall style.

The practical difference is less about basic fitment and more about the specific product character within the same size. A Q60 owner comparing these tires should look at the exact speed rating, load rating, and approved rim-width range for the wheel already on the car, then choose the product whose specs best align with that setup. Staying inside the same 245/45R18 size preserves the fitment baseline while letting you compare tire series more closely.

Approved rim width depends on the exact 2015 Infiniti size. 225/55R17 works across 6.0 to 9.0 inches depending on product, 245/40R19 uses 8.0 to 9.5, 225/45R19 uses 7.0 to 8.5, 225/50R18 uses 6.0 to 8.0, 245/45R18 uses 7.5 to 9.0, and 245/40R20 uses 8.0 to 9.5. Some sizes, such as 265/35R19 and 245/50R18, have fewer published rim-width details across the available choices.

The key is to treat the tire and wheel as a matched pair rather than assuming any tire with the right diameter will work on any wheel. Infiniti’s 2015 lineup covers several widths and aspect ratios, especially on Q50 and Q60 applications, so the same rim diameter does not guarantee the same wheel width. Before replacing tires, measure or verify the actual wheel and compare it to the approved range for the exact tire you intend to use.

The 2015 Infiniti sizes here are modern radial fitments, and their size markings do not identify tube-type construction. They are presented as contemporary radial products rather than tube-type collector applications, which is consistent with how late-model Infiniti wheels and tires were designed to be used.

Even so, the right approach is to verify the wheel itself before final installation. A damaged bead seat, corrosion at the rim, or an older aftermarket wheel can create sealing issues that have nothing to do with the tire size. If your 2015 Infiniti still has original wheels in sound condition, these radial sizes are the kind typically used in tubeless service, but the wheel and valve hardware should always be inspected at the same time.

A stored 2015 Infiniti should be kept out of direct sunlight, away from electric motors or ozone-producing equipment, and off damp surfaces whenever possible. Clean, dry storage with stable temperatures is kinder to tire rubber than a hot garage corner or outdoor cover situation. Because these are low-profile modern radials on many applications, long periods of inactivity can still create temporary flat spotting even though they are generally less prone to it than vintage bias-ply tires.

Move the car periodically so the tires do not sit in one footprint for months at a time, and keep inflation pressure checked during storage rather than assuming it will hold indefinitely. If the car will be parked for a very long stretch, tire cradles or properly placed stands can reduce stress on the casing. Owners who drive seasonally should also inspect sidewalls before the first spring outing, especially on 19- and 20-inch fitments with shorter sidewalls.

On a 2015 Infiniti, age matters as much as tread depth, and often more. Collector and low-mileage cars can keep plenty of tread while the rubber hardens or begins to crack with time. A sensible rule is to start evaluating tires carefully around five to seven years of age and to treat ten years as a strong replacement point, regardless of remaining tread, using the DOT date code on the sidewall to confirm age.

That matters especially on 2015 Infiniti cars that may be driven less often than ordinary commuter vehicles but still carry performance-oriented fitments. A tire that looks acceptable at a glance can still lose wet-weather grip and ride quality as it ages. If the car is seeing highway use, spirited driving, or longer trips, an age-based replacement mindset is far wiser than relying on mileage alone.

Tires on a 2015 Infiniti should be inspected before every drive, with a more thorough check before any extended outing. Look for cracking, punctures, cuts, bulges, uneven wear, and any sign that the tire is losing pressure. On low-profile sizes such as 245/40R19, 265/35R19, and 245/40R20, sidewall damage from potholes or curb contact deserves especially close attention.

A monthly pressure check is a good baseline for a regularly driven car, but collector-use cars often need more vigilance because they sit longer between trips. Uneven wear can also point to alignment or suspension issues rather than a tire defect, which is worth addressing before fitting replacements. If the spare is still part of your road-trip plan, inspect its age and inflation too, because an overlooked spare can leave a well-maintained Infiniti stranded.

A 2015 Infiniti Q40 belongs to the modern radial era, so a radial tire is the original construction type to expect. Within this year and make, the Q40 uses 225/55R17, which places it on a 17-inch wheel rather than the larger-diameter packages seen on other 2015 Infiniti models. Original-equipment style expectations for a car of this age generally center on a contemporary blackwall radial look.

Owners pursuing a factory-faithful presentation should keep the size, construction, and overall sidewall appearance aligned with what a 2015 luxury sport sedan would have worn when new. A wide whitewall or other custom sidewall treatment can be an intentional style choice, but it changes the visual authenticity of the car. For market-specific wheel and tire package verification, Infiniti specialists and marque forums remain the best resources for checking exact build combinations.

Correct tire fitment can matter in a judged setting for a 2015 Infiniti, even though these cars are newer than the traditional concours field. Size, construction, and sidewall appearance all influence whether the car looks factory-correct. A mismatched wheel diameter, an incorrect profile, or an overtly custom sidewall treatment can stand out quickly on a modern Infiniti because the original design language was clean and restrained.

For most show-oriented owners, the safest path is to match the model’s correct size and use a blackwall radial that suits the car’s period and market position. Custom sidewalls such as wide whitewall, redline, or raised white letters may appeal for personal taste, but they shift the car away from stock visual authenticity. If the event has strict judging standards, check its rulebook or consult Infiniti-focused clubs before finalizing the tire choice.

On a 2015 Infiniti, Blackwall is the mainstream contemporary appearance and the closest match to how a modern luxury or sport sedan would normally present. Custom sidewall treatments do exist in certain sizes, including Wide Whitewall on 225/55R17, RWL on 245/40R20, and both RWL and Redline on 245/50R18. The tire size and construction remain the primary fitment concerns, but the sidewall style changes the car’s visual identity immediately.

For a restoration-minded or factory-look owner, Blackwall is usually the appropriate direction. A whitewall, redline, or raised white letter sidewall can suit a personalized build, yet it gives the car a stronger aftermarket or custom tone than Infiniti intended in 2015. The decision comes down to whether the goal is authenticity or self-expression, and that choice should be made only after the correct model-specific size has been confirmed.

The 2015 Infiniti sizes here are modern radial tires, and many carry W or Y speed ratings. W is rated to 168 mph, while Y is rated for 186 mph and above, depending on the product and size. That means the tires themselves are well within normal U.S. highway use when they are properly inflated, in sound condition, and matched to the correct model and wheel diameter.

Real-world safety still depends on far more than the speed symbol on the sidewall. Tire age, pressure, alignment, brake condition, and suspension health matter just as much on a modern Infiniti, especially on lower-profile 19- and 20-inch combinations that react more sharply to road damage and setup problems. For everyday use, the most important step is choosing the correct size and maintaining the tires carefully rather than chasing a headline speed rating.

Inflation pressure for a 2015 Infiniti should follow the vehicle placard or owner’s manual first, because factory pressure recommendations are vehicle-specific and tied to weight distribution and handling targets. Tire load-and-pressure figures vary by size where published: 225/55R17 reaches up to 1,819 pounds at 50 psi, 245/40R19 up to 1,653 pounds at 50 psi, 225/45R19 up to 1,565 pounds at 50 psi, 225/50R18 up to 1,709 pounds at 50 psi, 245/45R18 up to 1,764 pounds at 50 psi, and 245/40R20 up to 1,709 pounds at 50 psi.

Those figures are tire capacity limits, not a universal instruction to inflate every 2015 Infiniti tire to 50 psi. A Q40, Q50, Q60, Q70, and Q70L can each have different operating needs depending on model and wheel package. Use the car’s factory recommendation for normal service, then confirm that the tire itself is operating within its own rated limits. Never transfer a pressure assumption from one Infiniti size to another just because the brand is the same.

Before a longer drive in a 2015 Infiniti, inspect all four tires for cracking, cuts, bulges, irregular wear, and visible punctures, then verify cold inflation pressure. Pay close attention to the sidewalls on lower-profile sizes such as 245/40R19, 265/35R19, and 245/40R20, since impact damage is easier to miss than a simple tread issue. If the car has sat for a while, confirm that none of the tires has developed a severe flat spot or pressure loss.

The tires are only one part of the trip-prep routine on a performance-luxury car, so it also makes sense to check alignment feel, brake response, and the condition of the spare if one is carried. A well-chosen tire cannot compensate for neglected suspension or braking hardware. Getting ahead of those issues is especially important on 2015 Infiniti models that mix sport-sedan handling with larger-diameter wheel packages and shorter sidewalls.