2006 Infiniti Tire Fitment Guide

2006 Infiniti vehicles use nine sizes across four model lines: 225/50R17, 235/50R17, 225/45R18, 245/45R18, 225/40R19, 245/40R19, 215/55R17, 235/45R18, and 225/55R17. The G35 uses eight of those sizes, the M35 uses 245/45R18 and 245/40R19, the M45 uses 245/45R18 and 245/40R19, and the Q45 uses 225/55R17, 245/45R18, and 245/40R19. Rim diameters span 17, 18, and 19 inches, and recommended rim-width ranges vary by size, from 6.0-7.5 inches on 215/55R17 up to 8.0-9.5 inches on 245/40R19.

That means year and make alone are not enough for a confident selection on a 2006 Infiniti. Start by confirming the exact model, then verify whether the car is on 17-, 18-, or 19-inch wheels, because that quickly narrows the options. If the car has replacement wheels, compare the actual tire size on the sidewall and the wheel diameter before choosing a product. That is especially important on the G35, which appears with the widest spread of fitments.

On a 2006 Infiniti, 245/45R18 is a metric radial size. The 245 is the nominal section width in millimeters, 45 is the aspect ratio, meaning the sidewall height is 45 percent of the section width, R means radial construction, and 18 is the wheel diameter in inches. This size appears across the G35, M35, M45, and Q45, making it one of the most widely shared fitments in the 2006 Infiniti range.

Understanding that code helps you avoid mixing up tires that may look similar but fit different wheels or have different overall proportions. A 245/45R18 cannot be substituted casually for a 245/40R19, because the wheel diameter changes from 18 to 19 inches. On a 2006 Infiniti, the code on the sidewall is the quickest way to match the car to the correct shared fitment, especially when multiple models overlap.

No, 2006 Infiniti models do not all use the same tire size. The M35 and M45 share the same two sizes, 245/45R18 and 245/40R19, and the Q45 overlaps with those while also using 225/55R17. The G35 covers the broadest range with eight sizes, including several 17- and 18-inch fitments that do not carry over to the larger sedans.

The practical takeaway is that a 2006 Infiniti buyer should identify the model before comparing brands or tread designs. Shared sizes make shopping easier for the M35, M45, and many Q45 applications, but the G35 requires more careful confirmation because wheel-package differences create multiple correct answers. If the car has been modified, checking the actual wheel diameter and sidewall size is just as important as knowing the badge on the trunk.

Most 2006 Infiniti sizes are available as Blackwall radials, which match the modern sport-luxury look expected on cars from this era. The one exception is 225/55R17, a Q45 size that also appears in a Wide Whitewall radial alongside Blackwall performance options. That gives the Q45 owner a styling choice that does not exist across the rest of the 2006 Infiniti range.

For a factory-appropriate appearance on a 2006 Infiniti, Blackwall is the natural visual choice across G35, M35, M45, and most Q45 applications. A whitewall on a Q45 is more of a custom or stylistic decision than a typical original-look selection for a 2006 Japanese luxury sedan. If appearance matters as much as fitment, choose the sidewall style first only after confirming that the size itself is correct for the car.

BFGoodrich covers every 2006 Infiniti size represented here, while Nitto appears in several of the shared and G35-specific performance sizes, including 225/50R17, 225/45R18, and 245/45R18. Across the range, BFGoodrich spans g-Force COMP-2 A/S, g-Force Sport COMP-2, g-Force Phenom T/A, and one Silvertown Radial whitewall application in 225/55R17. Nitto’s presence is narrower, but it adds another brand choice in key metric radial performance sizes.

That brand split matters most if you are trying to keep the same make of tire on all four corners or if you want to compare performance-oriented radial lines within one exact size. On a 2006 Infiniti with staggered or model-specific fitments, it is wise to make sure the same series exists in both front and rear sizes before finalizing a selection. Brand choice comes after size and wheel diameter, not before.

On several 2006 Infiniti sizes, BFGoodrich offers both g-Force COMP-2 A/S and g-Force Phenom T/A, and the key differences show up in speed and load markings rather than fitment. In 245/45R18, for example, the COMP-2 A/S carries a 96W marking while the Phenom T/A carries 100Y, and both fit 7.5-9.0 inch rims. In 245/40R19, the COMP-2 A/S appears as 94W while the Phenom T/A is 98Y, again on the same 8.0-9.5 inch rim-width range.

For a 2006 Infiniti owner, that means the two series can share the same basic size fitment while differing in rated capability and product character. It is worth comparing the exact sidewall marking, load index, and speed letter rather than assuming every tire in the same size is interchangeable in specification. If your car is driven regularly at modern freeway speeds, consistency across all four tires matters as much as choosing the right size.

Rim-width ranges for 2006 Infiniti tires vary by size. The 215/55R17 fits 6.0-7.5 inch rims, 225/50R17 and 225/55R17 fit 6.0-8.0 inch rims, 235/50R17 fits 6.5-8.5 inch rims, 225/45R18 fits 7.0-8.5 inch rims, 235/45R18 and 245/45R18 fit 7.5-9.0 inch rims, 225/40R19 fits 7.5-9.0 inch rims, and 245/40R19 fits 8.0-9.5 inch rims. Those ranges are broad enough to cover many factory and aftermarket wheel applications, but they are not all the same.

The main point is to verify both the tire size and the actual wheel width before mounting a replacement on a 2006 Infiniti. Two tires can share the same wheel diameter and still want different wheel widths for proper sidewall shape and tread support. That matters most when a car has aftermarket wheels, because diameter alone does not guarantee the wheel is correct for the intended tire size.

The 2006 Infiniti sizes here are modern radial applications and do not carry tube-type markings. Their sidewall sizing and product construction align with tubeless passenger-car radials rather than vintage tube-type tires. That is consistent across the performance-oriented 17-, 18-, and 19-inch sizes used by the G35, M35, M45, and Q45.

Even so, wheel condition still matters on a 2006 Infiniti. A bent rim, corroded bead seat, or failing valve stem can create the same air-loss symptoms many people wrongly blame on the tire itself. If the car has older factory wheels or aftermarket wheels of unknown age, inspect the sealing surfaces and valve hardware when the tires are mounted.

Original 2006 Infiniti wheels cannot be treated as universal across all nine sizes, because the lineup uses three different rim diameters: 17, 18, and 19 inches. A 17-inch wheel only accepts the 17-inch sizes, an 18-inch wheel only accepts the 18-inch sizes, and a 19-inch wheel only accepts the 19-inch sizes. Several models share 245/45R18 and 245/40R19, but that overlap exists only when the wheel diameter matches.

That makes wheel identification the first physical check before buying tires for a 2006 Infiniti. If the car still wears its original wheels, the existing sidewall size and wheel diameter usually answer the question quickly. If the car has been upgraded or mixed with take-off wheels from another Infiniti model, confirm the wheel width too, because not every tire size suits every wheel within the same diameter.

A 2006 Infiniti should be stored on a clean, dry surface away from direct sunlight, electric motors, battery chargers, welders, and other ozone-producing equipment. Keep the tires properly inflated, avoid long exposure to standing moisture, and move the car periodically so one contact patch does not sit in the same place for months. Modern radials resist storage flat-spotting better than old bias-ply designs, but they still benefit from regular repositioning.

For longer seasonal storage, many owners either roll the car every few weeks or use stands correctly to reduce constant load on one section of the tire. That helps preserve sidewall shape and can reduce vibration when the car returns to the road. On a 2006 Infiniti with lower-profile 18- or 19-inch tires, protecting the sidewalls from UV and ozone is especially worthwhile because there is less sidewall height to disguise early aging.

On a low-use collector or pleasure-driven 2006 Infiniti, tire age matters more than mileage. A sound rule is to begin close inspection once tires reach the five- to seven-year range and to treat the ten-year point as a serious replacement threshold regardless of remaining tread. The DOT date code on the sidewall tells you when each tire was made, and that date is more useful than odometer readings for cars that spend much of the year parked.

A 2006 Infiniti can easily accumulate old tires with plenty of tread if it is driven only on weekends or to events. Sidewall cracking, hardening rubber, vibration, and reduced wet-weather confidence can all appear before the tread looks worn out. Matching age across a full set is also important, because one fresh tire and three much older tires can create uneven behavior even when the sizes are correct.

Tires on a 2006 Infiniti should be checked before every drive and given a more thorough inspection before any extended trip. Look for sidewall cracking, punctures, cuts, bulges, uneven wear, and any sign that the tire is losing pressure between outings. Because these are performance-oriented radial sizes, underinflation or irregular wear can change steering feel and ride quality sooner than many owners expect.

A monthly pressure check is a good baseline even if the car is rarely driven, and a hands-on inspection before a highway run is smart insurance. Pay attention to the inner shoulder as well as the visible outer tread, especially on cars with sport suspension alignment or wider rear fitments. If the car has been sitting for a long period, inspect the spare and valve stems at the same time rather than focusing only on the four road tires.

The 2006 Infiniti sizes here are modern radial passenger-car tires with W and, in some sizes, Y speed ratings. W is rated to 168 mph, while Y is rated to 186 mph, and those markings appear in shared sizes such as 245/45R18 and 245/40R19 as well as several G35-specific fitments. At ordinary U.S. highway speeds, the tire’s rated ceiling is far above normal use, provided the tire is in good condition and correctly inflated.

Real-world safety in a 2006 Infiniti depends just as much on age, inflation, alignment, and overall vehicle condition as on the speed letter molded into the sidewall. A cracked, underinflated, or poorly matched tire is a bigger concern than whether the car carries a W or Y marking during typical freeway driving. For long-distance use, keep all four tires closely matched in size, condition, and capability.

Inflation pressure for a 2006 Infiniti should follow the vehicle’s factory tire placard or owner’s manual for the exact model and wheel package, not a generic number borrowed from another Infiniti size. Some tire sizes also carry maximum load and pressure figures on the tire itself, such as 1,764 pounds at 50 psi for certain 245/45R18 products and 1,653 pounds at 50 psi for some 245/40R19 products. Those numbers describe the tire’s rated capacity ceiling, not the everyday cold inflation setting you automatically use on the car.

That distinction matters because ride, wear, and handling on a 2006 Infiniti can change quickly when inflation drifts too high or too low. The correct routine is to start with the factory recommendation for your exact model and wheel diameter, then confirm that the chosen tire meets the load needs of the car. Never transfer a pressure figure from a 17-inch Q45 fitment to an 18- or 19-inch G35 or M-car tire just because the brand is the same.

Before a longer trip in a 2006 Infiniti, inspect each tire for cracking, cuts, bulges, punctures, and uneven wear, then verify cold inflation pressure and make sure the tread is wearing evenly across the contact patch. Check the spare as well, since many cars of this age still carry an original or long-neglected emergency tire. If the car has 18- or 19-inch fitments, look closely at the wheel lips for impact damage that could affect sealing or balance.

A tire check should be part of a broader pre-drive routine on a 2006 Infiniti that also includes brakes, fluids, battery condition, and suspension feel. Tires are often the first place an infrequently driven car reveals age-related problems, especially after months of storage. Catching a sidewall issue or slow leak before departure is far easier than dealing with vibration or a pressure loss once the trip is underway.