2009 Infiniti M45 Tires

A 2009 Infiniti M45 uses either 245/45R18 or 245/40R19, depending on sub-model. The Luxury and X models use 245/45R18 radial tires, while the Sport model uses 245/40R19 radial tires. Both are modern metric radial sizes, but they are tied to different wheel diameters.

Choosing the right one starts with confirming the exact trim and checking the wheel diameter on the car. That step matters because an 18-inch tire and a 19-inch tire are not interchangeable simply because they share the same section width. If the car has aftermarket wheels, verify the actual wheel size before comparing tire options.

The 2009 Infiniti M45 uses either an 18-inch or 19-inch rim, depending on sub-model. Luxury and X models use the 245/45R18 fitment on an 18-inch wheel, while the Sport uses the 245/40R19 fitment on a 19-inch wheel. Tire choice follows that wheel diameter first.

Rim diameter is the first thing to confirm because the two primary tire sizes are built for different wheels. Once diameter is verified, compare the tire’s recommended rim-width range with the wheel on the car. That is especially important if the M45 has been fitted with replacement wheels that may differ from the original setup.

No. The 2009 Infiniti M45 Luxury and M45 X share the 245/45R18 radial size, but the M45 Sport uses 245/40R19. The size difference also means a wheel-diameter difference, so the Sport does not share the same primary fitment as the other covered sub-models.

That distinction matters when replacing tires on a car that may have changed hands or been modified over time. Checking the sub-model badge is helpful, but the wheel itself should also be measured or confirmed visually. A car wearing the wrong wheel diameter can easily lead to choosing the right trim name but the wrong tire.

Start by making sure the car is an M45 Luxury or M45 X, or that it currently runs the correct 18-inch wheels. In 245/45R18, available choices include BFGoodrich and Nitto blackwall radial tires, with series such as g-Force Comp 2 AS, g-Force Sport Comp 2, g-Force Phenom T/A, and NT555 G2.

Once size is confirmed, compare rim-width compatibility, load figures where stated, and the overall character of each tire series. Some owners will prioritize a touring-friendly street setup, while others may want a more performance-focused option. Matching the tire to the wheel and the way the car is actually driven is more useful than choosing by brand name alone.

The 2009 Infiniti M45 tire options here come from BFGoodrich and Nitto. The 245/45R18 fitment includes both brands, while the 245/40R19 fitment is represented by BFGoodrich choices. That means brand availability changes somewhat depending on whether the car uses the 18-inch or 19-inch setup.

Brand is only one part of the decision, so it helps to compare each tire by its actual size, series, and wheel-fit range. A buyer with an M45 Sport may be comparing only BFGoodrich options in 19-inch form, while an 18-inch car opens the door to Nitto as well. Start with fitment, then narrow by product character.

Available tire series for the 2009 Infiniti M45 include BFGoodrich g-Force Comp 2 AS, BFGoodrich g-Force Sport Comp 2, BFGoodrich g-Force Phenom T/A, and Nitto NT555 G2. Not every series appears in both primary sizes, so the exact wheel and trim setup still controls which choices are relevant.

Series names matter because they help separate all-season, sport-oriented, and performance-focused product lines within the same basic fitment. After identifying the correct size, compare the series that are actually offered in that size rather than assuming every line is available across both wheel diameters. That approach keeps the search tied to the car’s actual configuration.

Yes. Even on a newer collector-era luxury sport sedan, correct tire fitment matters because the 2009 Infiniti M45 uses different sizes for different sub-models. Luxury and X models use 245/45R18, while the Sport uses 245/40R19. Preserving the proper wheel-and-tire relationship helps maintain the car’s intended stance and presentation.

Appearance is only part of the equation, since the wrong diameter can also complicate wheel and clearance compatibility. A restoration-minded owner should confirm the trim, wheel size, and whether the car still carries its original-style setup before choosing tires. That keeps the result visually consistent without assuming every surviving car remains exactly as delivered.

For the 2009 Infiniti M45, the primary fitments are radial tires, so construction choice is less about bias-ply versus radial appearance and more about keeping the correct modern performance-sedan look. The available options use blackwall styling, which suits the understated, late-2000s sport-luxury presentation of this model.

A restoration-oriented owner will usually get the most coherent look by keeping the proper size on the correct 18-inch or 19-inch wheel rather than chasing a different tire profile. Sidewall height and wheel diameter have a strong visual effect on this car, especially between Luxury/X and Sport trims. Confirming that relationship helps the finished car look properly sorted.

Yes. Wheel changes, suspension lowering, spacer use, and body or alignment changes can all affect tire fitment on a 2009 Infiniti M45. That matters here because the car already uses two different factory-style wheel diameters across its sub-model range, so an altered setup can blur the line between original trim fitment and current wheel fitment.

A modified car should be checked at the wheel before a tire is chosen. Confirm the actual rim diameter and width, then look at clearance around the fenders, suspension, and steering range. Even when the tire size sounds close to stock, the wrong wheel setup can create rubbing or compatibility issues that a trim badge alone will not reveal.

Before road use, inspect the wheel size, tire pressure, and the general condition of the suspension and alignment-related wear points. A 2009 Infiniti M45 should also be checked for any signs of previous rubbing, uneven old-tire wear, or damage at the wheel lip that could affect how the new tires seat and run.

It also helps to verify that all four tires match the intended size for the car’s current setup and that there is no interference at full steering lock. After installation, pay attention to vibration, pull, or unusual noise on the first drive. Those early signs can point to fitment, balance, or alignment issues worth correcting promptly.

Tires on a 2009 Infiniti M45 should be inspected regularly, especially if the car is driven infrequently or stored for long periods. Check pressure, tread wear, cuts, sidewall cracking, bulges, and signs of air loss. A performance-oriented luxury sedan can mask tire aging until the car is back at highway speed.

Seasonal inspections are a sensible baseline for a collector-used or lower-mileage car, with another look before any longer trip. Tires that appear fine while parked can still age out or develop issues from storage, heat, or time. Regular inspection helps catch problems early and confirms the car is still running the right size on the right wheels.