2012 Infiniti Tire Fitment Guide

2012 Infiniti vehicles use seven tire sizes: 225/55R17 for G25 and some G37 applications, 225/45R19 for G37, 225/50R18 for G37, 245/40R19 for G37, 245/45R18 for G37, 245/50R18 for M35h, M37, and M56, and 245/40R20 for M37 and M56. Rim diameters across the range are 17, 18, 19, and 20 inches. Where rim-width guidance is available, 225/55R17 fits 6.0 to 9.0 inches depending on the tire, 225/45R19 fits 7.0 to 8.5, 225/50R18 fits 6.0 to 8.0, 245/40R19 fits 8.0 to 9.5, and 245/45R18 fits 7.5 to 9.0.

That spread means year and make alone are not enough for a correct selection. A G37 owner may need to confirm whether the car uses 17-, 18-, or 19-inch wheels, and M37 or M56 owners need to separate 18-inch cars from 20-inch cars before moving any further. If the car is already fitted with aftermarket wheels, compare the tire sidewall marking to the wheel diameter on the car rather than assuming the original configuration.

On a 2012 Infiniti, 225/55R17 is a modern metric radial size. The 225 is the nominal section width in millimeters, 55 is the aspect ratio, R means radial construction, and 17 is the wheel diameter in inches. In this year-make range, that size appears on the G25 and on certain G37 applications. Available versions include BFGoodrich Blackwall performance radials as well as a BFGoodrich Silvertown Radial with a 1.50-inch whitewall.

That combination makes 225/55R17 one of the more versatile sizes in the 2012 Infiniti family. It can serve an owner keeping a G sedan close to a contemporary blackwall look, or someone building a more personalized appearance with a whitewall treatment. Before choosing among the variations, verify whether your car uses the 17-inch package or one of the lower-profile 18- or 19-inch G37 options.

No. 2012 Infiniti models split into several distinct fitment groups. The G25 uses 225/55R17, the G37 spans five sizes across 17-, 18-, and 19-inch wheel packages, the M35h uses 245/50R18, the M37 uses either 245/50R18 or 245/40R20, and the M56 uses either 245/50R18 or 245/40R20. Every size in the range is radial, but the wheel diameters and section widths change significantly from one model to another.

The practical lesson is to identify the exact model first, then confirm the wheel diameter already on the car. That matters most on G37, M37, and M56 models, where multiple factory-size paths exist. If you are checking a recently purchased car, read the sidewall and wheel directly rather than relying only on a badge or a prior owner’s memory.

2012 Infiniti tire options are not limited to one appearance. Most sizes, including 225/45R19, 225/50R18, 245/40R19, and 245/45R18, are available in Blackwall form. The shared 225/55R17 size also appears as a Wide Whitewall, while 245/50R18 comes in RWL and Redline versions, and 245/40R20 is available in both Blackwall and RWL. Those choices create very different visual effects even when the core size remains correct.

For a stock late-model Infiniti look, Blackwall is the natural visual match. Whitewall, redline, or raised white letter treatments suit owners who are deliberately steering the car toward a custom or retro-inspired presentation rather than factory-style appearance. If appearance matters as much as fitment, choose the size first, then compare which sidewall styles exist within that exact size instead of assuming every style is offered across the whole range.

Three brands cover the 2012 Infiniti range here: BFGoodrich, Nitto, and Pro-Trac. BFGoodrich appears across 225/55R17, 225/45R19, 225/50R18, 245/40R19, 245/45R18, and 245/40R20. Nitto appears in 245/45R18 and 245/40R20, while Pro-Trac covers 245/50R18 and 245/40R20. Brand coverage follows the size more than the vehicle name, so two Infiniti models with different wheel packages may not share the same brand choices.

That means brand selection often starts after you confirm the exact tire size on the car. A G25 owner using 225/55R17 will see a different mix from an M56 owner on 245/40R20, even though both are shopping within the same year and make. If you care about keeping all four tires in the same family, check your front and rear sizes carefully on cars that may use staggered fitments.

On several 2012 Infiniti sizes, BFGoodrich g-Force Sport Comp 2 and BFGoodrich g-Force Phenom T/A share the same basic radial construction and Blackwall appearance, but their sidewall markings and service ratings are not always identical. In 225/45R19, for example, the Sport Comp 2 carries a 96W rating while the Phenom T/A carries a 96Y rating. In 245/45R18, the Sport Comp 2 appears as 96W while the Phenom T/A appears as 100Y, and the two also differ slightly in weight.

For the buyer, the comparison comes down to matching the exact size, load index, and speed symbol that best aligns with the car’s use and configuration rather than choosing by series name alone. If you are replacing tires on a G37 with a wider rear fitment, compare the service description on the tire sidewall to what is already on the car so the new set stays consistent from side to side and axle to axle.

Rim-width guidance for 2012 Infiniti tires depends on the exact size. 225/55R17 fits 6.0 to 9.0 inches depending on the tire chosen, 225/45R19 fits 7.0 to 8.5 inches, 225/50R18 fits 6.0 to 8.0 inches, 245/40R19 fits 8.0 to 9.5 inches, 245/45R18 fits 7.5 to 9.0 inches, and 245/40R20 fits 8.0 to 9.5 inches. The 245/50R18 products here do not carry a rim-width range in the same way, so that size still deserves a wheel-by-wheel check before installation.

Those ranges matter most when a car has aftermarket wheels or when a buyer is comparing a standard tire to a more stylized sidewall option. Matching the tire to the wheel width keeps the sidewall profile and bead seating within the tire maker’s intended operating window. If the wheel width on your car falls near either end of the range, compare the exact tire’s recommendations before making a final choice.

The 2012 Infiniti sizes here are modern radial applications, and none of the size markings indicate tube-type construction. The sidewall markings use radial metric formats such as 225/55R17, 245/45ZR18, and 245/40ZR20, which align with tubeless passenger-car fitments rather than vintage tube-type designs. No size in this group uses antique, numeric bias-ply, or alphanumeric tube-era sizing.

That does not remove the need to inspect the wheels themselves. A bent rim, corrosion at the bead seat, or an aging valve stem can still cause air loss on a tubeless setup. When mounting replacement tires on a 2012 Infiniti that has seen years of service, it is smart to inspect the wheels and replace valve stems at the same time so the new tires start on a clean foundation.

No. Original 2012 Infiniti wheels are size-specific because the tire range spans 17-, 18-, 19-, and 20-inch diameters. A 225/55R17 tire belongs on a 17-inch wheel, a 225/50R18 or 245/50R18 on an 18-inch wheel, a 225/45R19 or 245/40R19 on a 19-inch wheel, and a 245/40R20 on a 20-inch wheel. The M37 and M56 can appear on either 18-inch or 20-inch packages, while the G37 can appear on 17-, 18-, or 19-inch combinations.

That means the wheel already on the car is your first fitment checkpoint. If you are moving between tire sizes, the change is only practical when the wheel diameter matches and the tire also falls within the correct width range for that wheel. Owners of used cars should confirm whether the wheels are factory or aftermarket before assuming the original Infiniti configuration is still in place.

A 2012 Infiniti should be stored in a cool, dry, dark space with the tires protected from direct sunlight, electric motors, welders, battery chargers, and other ozone-producing equipment. Keep the tires properly inflated, avoid parking on damp soil or oily concrete, and move the car periodically so one contact patch does not sit in the same position for months at a time. Because every size in this range is radial, storage flat-spotting is usually less pronounced than with older bias-ply tires, but long static periods still age the rubber.

For seasonal or collector use, a short drive every few weeks helps the tires flex and circulate protective compounds through the casing. If the car will remain parked for a long stretch, support it in a way that reduces prolonged loading without letting the suspension hang improperly. A clean storage environment does as much for tire life as low mileage, especially on luxury cars that may look fresh long after the rubber has begun to age.

Tires on a 2012 Infiniti should be judged by age as much as tread depth. For collector, low-mileage, or occasional-use cars, a good rule is to begin evaluating the tires closely around five to seven years and to treat ten years as a serious replacement threshold regardless of remaining tread. The DOT date code on the sidewall gives the production week and year, which matters more than the odometer on a lightly driven G or M sedan.

Luxury cars often hide tire aging because they may be garage kept and driven gently, yet sidewall cracking, hardening, or internal fatigue can still develop over time. If a 2012 Infiniti still wears an older matched set, inspect the date codes before assuming the tires are road-ready. Age-based decisions are especially important before highway use, long trips, or replacing only one axle on a car that has spent much of its life in storage.

Tires on a 2012 Infiniti deserve a quick inspection before every drive and a more careful check before any longer outing. Look for cracking, cuts, punctures, bulges, uneven shoulder wear, and any sign that the tire is losing pressure between drives. On lower-profile sizes such as 225/45R19, 245/40R19, and 245/40R20, it is also wise to watch closely for damage from potholes or curb contact because the shorter sidewall offers less visual cushioning.

A brief walkaround catches small issues before they become trip-ending problems. Include tread depth, valve stem condition, and air pressure in the routine, especially if the car spends long periods parked between drives. If one tire consistently reads low, have the wheel and valve checked rather than topping it off repeatedly, since slow leaks can come from bead-seat corrosion or minor wheel damage as much as from the tire itself.

Yes, the 2012 Infiniti tire sizes here are highway-capable modern radials, and many carry W or Y speed ratings depending on the exact product. W-rated tires are rated to 112 mph, while Y-rated tires are rated to 186+ mph. Some sizes, such as 225/45R19, 245/40R19, 245/45R18, and 245/40R20, offer both W- and Y-rated choices within the same size family. Those ratings are well beyond ordinary interstate speeds when the tires are in good condition and properly inflated.

Real-world safety depends at least as much on the condition of the car as on the tire’s speed symbol. A 2012 Infiniti is modern enough to cruise comfortably, but alignment, suspension wear, brake condition, and tire age still matter more than chasing the highest letter on the sidewall. For normal road use, focus first on the correct size, even wear, healthy date code, and stable pressure retention rather than the most aggressive speed rating available.

Inflation pressure on a 2012 Infiniti should start with the vehicle’s factory placard or owner’s manual, then be checked against the tire maker’s service description and maximum-pressure marking. Where service data appears in these sizes, examples include 225/55R17 at up to 1819 pounds at 50 psi, 225/45R19 at up to 1565 pounds at 50 psi, 225/50R18 at up to 1709 pounds at 50 psi, 245/40R19 at up to 1653 pounds at 50 psi, 245/45R18 at up to 1764 pounds at 50 psi, and 245/40R20 at up to 1709 pounds at 50 psi.

Those figures are tire capability marks, not automatic everyday operating pressures. The correct running pressure for your G or M model depends on the vehicle calibration, the size on the car, and whether the fitment is front or rear in a staggered arrangement. Use the car’s recommended cold inflation pressure for daily driving, then confirm that the tire selected carries suitable load capacity for that application.

Before a longer drive in a 2012 Infiniti, inspect all four tires and the spare for visible cracking, cuts, punctures, bulges, and uneven wear, then verify cold inflation pressure. Pay special attention to lower-profile sizes such as 225/45R19, 245/40R19, and 245/40R20 because they can hide impact damage that only shows up when the sidewall is viewed closely. Also check valve stems, wheel condition, and whether the tires are all the same size and service type across each axle.

A tire check should be part of a broader pre-trip routine on any older luxury car, even one as modern as a 2012 Infiniti. Confirm the jack and lug tools are present, make sure the spare is usable, and look over brakes, fluids, and battery condition before relying on the car for distance travel. Catching a weak tire or damaged wheel in the garage is far easier than dealing with vibration or air loss on the roadside.