The 2012 Infiniti M37 sits in that era when Infiniti blended luxury-sedan comfort with a distinctly athletic rear-drive character. It appeals to buyers who want a modern performance-oriented four-door that still feels connected to the road, especially in Sport trim. Tire fitment depends on configuration, with 245/50R18 radial tires used on the Luxury and M37 X, while the Sport moves to a 245/40R20 radial setup. That split also changes the look of the car, since available choices include blackwall, redline, and raised white letter styles across different series. The right choice starts with confirming the exact sub-model and wheel diameter already on the car.
Which Tire Size Is Right for The 2012 Infiniti M37
Two primary tire sizes apply to the 2012 Infiniti M37, and the correct one depends on sub-model and wheel diameter. The Luxury and M37 X use an 18-inch radial tire, while the Sport uses a 20-inch radial tire. Before comparing brands, sidewall styles, or tire series, the first step is confirming whether the car has the 18-inch or 20-inch wheel setup tied to its specific trim.
245/50R18 is a metric radial size with a 245-millimeter section width, a 50-series aspect ratio, and fitment for an 18-inch rim. On the 2012 Infiniti M37, this size suits the Luxury and M37 X and keeps the car in a modern radial construction appropriate for everyday road use. Available choices in this size include Pro-Trac Street Pro III tires with either raised white letter or redline sidewall styling. It is the right size to evaluate when the car has the factory 18-inch wheel format or an equivalent wheel setup that matches the required dimensions.
245/40R20 is a metric radial size that uses the same 245-millimeter nominal width but pairs it with a lower 40-series profile on a 20-inch rim. On the 2012 Infiniti M37, this size belongs to the Sport model and gives that trim its larger-wheel, lower-profile tire presentation. Product choices include blackwall performance-oriented options from BFGoodrich and Nitto, along with Pro-Trac Street Pro III tires in raised white letter and redline form. This is the size to consider only after confirming the car is a Sport model or already carries the correct 20-inch wheel setup.
Sub-model fitment matters on the 2012 Infiniti M37 because wheel diameter changes with the trim. The Luxury and M37 X share one tire size, while the Sport uses a different lower-profile size on a larger rim, so confirming the exact version of the car is the first step before comparing tires.
1
2012 Infiniti M37 Luxury
The 2012 Infiniti M37 Luxury uses the 245/50R18 radial tire size on an 18-inch wheel. That makes tire selection more about sidewall appearance and product character than sorting through multiple fitments, provided the car still has the correct wheel setup.
The 2012 Infiniti M37 Sport uses the 245/40R20 radial size on a 20-inch wheel, giving it a distinct fitment from the other M37 versions. Tire selection here centers on confirming the larger wheel diameter first, then comparing blackwall, redline, or raised white letter options within the proper size.
The 2012 Infiniti M37 X shares the 245/50R18 radial tire size with the Luxury model. Once that 18-inch fitment is confirmed, the main decision becomes choosing the tire style and series that best matches the car's appearance and intended road use.
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 2012 Infiniti M37 Tires for Sale
Available 2012 Infiniti M37 tire choices vary by trim, wheel diameter, brand, tire series, and sidewall styling. The 18-inch fitment centers on Pro-Trac Street Pro III with RWL or redline sidewalls, while the 20-inch Sport fitment adds blackwall options from BFGoodrich and Nitto.
Common 2012 Infiniti M37 tire questions usually come down to trim-specific size, 18-inch versus 20-inch wheel fitment, available sidewall styles, and how to choose among the radial tire options for road use and appearance.
Tire Size & Fitment
What tire size fits a 2012 Infiniti M37?
The 2012 Infiniti M37 uses two different tire sizes depending on sub-model. The M37 Luxury and M37 X use 245/50R18 radial tires, while the M37 Sport uses 245/40R20 radial tires. Both are modern metric radial sizes, but they fit different wheel diameters and should not be treated as the same setup.
The practical decision starts with identifying the exact trim and confirming the wheel diameter already on the car. An 18-inch M37 and a 20-inch M37 Sport require different tires, even though the nominal width is similar. If the car has aftermarket wheels, check the actual wheel size and clearance before choosing a replacement tire.
What size rim does a 2012 Infiniti M37 use?
A 2012 Infiniti M37 uses either an 18-inch or 20-inch rim, depending on sub-model. The Luxury and M37 X are tied to the 245/50R18 size, which uses an 18-inch rim, while the Sport uses 245/40R20, which fits a 20-inch rim. Rim diameter is a core part of the tire size and must match exactly.
Wheel diameter should be confirmed before looking at brands or sidewall style, because an 18-inch tire cannot be mounted on a 20-inch wheel and vice versa. If the car has been modified, inspect the stampings on the wheel or measure the setup rather than relying only on trim assumptions. Width and clearance also matter once diameter is confirmed.
Do all 2012 Infiniti M37 sub-models use the same tire size?
No, all 2012 Infiniti M37 sub-models do not use the same tire size. The Luxury and M37 X share 245/50R18 radial tires, while the Sport uses 245/40R20 radial tires. That means tire fitment is split between two wheel-and-tire packages rather than carried across the full model range.
This matters because the correct tire depends on more than just the model name on the trunk. A buyer should confirm whether the car is a Luxury, Sport, or X model and verify that the wheels still match that configuration. Cars with replacement wheels or suspension changes may need a closer check before any tire is selected.
Choosing the Right Tire
What should I consider when choosing a tire for a 2012 Infiniti M37?
Start with the correct size for the specific sub-model: 245/50R18 for the Luxury and M37 X, or 245/40R20 for the Sport. From there, compare the tire's construction, sidewall style, tire series, and any useful specifications such as rim-width guidance, weight, or load information where it is available.
A good choice depends on how the car is used and how you want it to look. Some owners will prefer a straightforward blackwall performance appearance, while others may want redline or raised white letter styling for a more distinctive presentation. Matching the tire to the wheel setup and the car's intended use matters more than choosing by appearance alone.
What sidewall styles are available for 2012 Infiniti M37 tires?
Sidewall style depends on the tire size and product line chosen for the 2012 Infiniti M37. Available styles include blackwall, redline, and RWL, which is raised white letter. The 18-inch 245/50R18 fitment is offered in redline and RWL through Pro-Trac Street Pro III, while the 20-inch 245/40R20 fitment adds blackwall options from BFGoodrich and Nitto.
That gives the M37 owner a real appearance choice without changing the underlying size requirement for the car. A blackwall tire keeps a more understated modern look, while redline or raised white letters create a more visual statement. Sidewall style should be chosen only after the correct size and wheel diameter have already been confirmed.
What brands offer tires for the 2012 Infiniti M37?
The 2012 Infiniti M37 has tire options from Pro-Trac, BFGoodrich, and Nitto, depending on size. Pro-Trac appears in both primary fitments through the Street Pro III series, while BFGoodrich and Nitto are available in the 245/40R20 Sport size. Brand choice therefore depends partly on whether the car uses the 18-inch or 20-inch setup.
Comparing brands makes the most sense after the correct size is settled. The 20-inch Sport fitment has the widest brand variety and includes multiple blackwall performance-oriented choices, while the 18-inch size is more focused around Pro-Trac styling options. It is smarter to compare each brand within the correct fitment than to shop the M37 as one universal package.
Restoration & Appearance
How does tire construction affect the appearance of a restored 2012 Infiniti M37?
On a 2012 Infiniti M37, construction is less about bias-ply versus radial appearance and more about choosing the right radial tire presentation for the trim. Both primary fitments are radial, so the visible appearance comes mainly from wheel diameter, profile, and sidewall style. A 245/50R18 Luxury or X model will present differently than a 245/40R20 Sport.
That means appearance decisions center on whether the car should look understated, sporty, or customized within the correct size. Blackwall tires keep a contemporary luxury-sport look, while redline or raised white letters change the visual character noticeably. For a clean restoration-oriented result, make sure the tire size matches the trim and the wheel package already on the vehicle.
Does correct tire fitment matter for a 2012 Infiniti M37 restoration?
Correct tire fitment matters on a 2012 Infiniti M37 because the model uses two distinct wheel-and-tire packages. The Luxury and M37 X use 245/50R18, while the Sport uses 245/40R20. Using the wrong size changes the visual balance of the car and can also create mounting or clearance issues if the wheel diameter does not match.
A restoration-minded owner should first decide whether the goal is to return the car to its original trim-specific presentation or maintain a later wheel change already on the vehicle. Once that is clear, select the tire by exact size, then by sidewall style and tire series. Checking actual wheel dimensions is especially important on cars that have changed hands several times.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2012 Infiniti M37?
Yes, modifications can affect tire fitment on a 2012 Infiniti M37 even when the replacement tire matches one of the correct stock sizes. Aftermarket wheels, changes in wheel width, altered offset, suspension lowering, and brake upgrades can all influence how an 18-inch or 20-inch tire sits in the wheelwell and how much clearance is available.
A modified car should be checked at full steering lock and through suspension travel before settling on a tire choice. Wheel diameter is only one part of fitment, and sidewall profile alone does not guarantee clearance. Any M37 with non-stock wheels should be measured carefully so tire selection reflects the actual setup rather than the factory trim label.
What should I inspect before driving a 2012 Infiniti M37 on new tires?
Before driving a 2012 Infiniti M37 on new tires, inspect wheel condition, valve stems, lug hardware, and overall tire pressure. It is also smart to confirm that the installed tire size matches the trim and wheel diameter, especially on a used car. A quick visual check for rubbing points, damaged suspension parts, or uneven prior tire wear can prevent problems.
The first miles after installation are a good time to pay attention to steering feel, vibration, and clearance over bumps or during parking-lot turns. Recheck inflation once the tires have settled in and make sure there is no contact with liners or suspension components. On a performance-oriented sedan like the M37, small fitment issues can become obvious quickly.
How often should tires on a 2012 Infiniti M37 be inspected?
Tires on a 2012 Infiniti M37 should be inspected regularly, not just when tread looks worn. A monthly check is a practical habit for pressure, visible cracking, cuts, punctures, bulges, and uneven wear. Cars that are driven less often still need inspection because age, storage conditions, and slow air loss can affect tire condition even with limited mileage.
A closer look before longer drives is especially worthwhile on a sedan that may alternate between daily use and extended parking. Inspect the inner and outer shoulders, since wear patterns can reveal alignment or suspension issues. Any time the car has been sitting, confirm pressure before road use, because underinflation can change handling and accelerate tire wear.
