The 2004 Infiniti Q45 sits in the era when flagship Japanese luxury sedans blended V8 power, rear-wheel-drive composure, and a distinctly understated design approach. Buyers looking at this car today are usually balancing refined road manners with the need to keep the car visually appropriate to its original character. Tire fitment depends on the exact version, with the Q45 Base using 225/55R17 radials and the Q45 w/Premium Pkg. using 245/45R18 radials. That creates two different selection paths, from modern blackwall performance-oriented tires to restoration-minded Silvertown Radial options in whitewall or redline for the 17-inch fitment. The right choice starts with confirming the sub-model and wheel diameter already on the car.
Which Tire Size Is Right for The 2004 Infiniti Q45
The 2004 Infiniti Q45 uses two primary tire sizes, and the correct one depends on the exact sub-model and wheel diameter. The Base model uses a 17-inch radial fitment, while the w/Premium Pkg. uses an 18-inch radial fitment, so identifying the package and confirming the wheels on the car should come before comparing brands, sidewall styles, or tire series.
A 225/55R17 tire is a metric radial size with a 225 millimeter section width, a 55-series aspect ratio, and fitment for a 17-inch rim. On the 2004 Infiniti Q45, this size belongs to the Base model and keeps the tire choice in a modern radial format. Available options include BFGoodrich blackwall performance-oriented lines as well as Silvertown Radial versions with wide whitewall or redline styling. This size makes sense for owners who need the 17-inch fitment and want to decide between contemporary appearance and a more distinctive period-inspired presentation.
A 245/45R18 tire is a metric radial size with a 245 millimeter section width, a 45-series aspect ratio, and fitment for an 18-inch rim. On the 2004 Infiniti Q45, this size is used on the w/Premium Pkg. configuration and points to a lower-profile radial setup than the 17-inch fitment. Choices in this size include BFGoodrich and Nitto blackwall tires across several performance-focused series. This is the size to evaluate when the car already has the correct 18-inch wheel package and the goal is to stay within the proper sub-model fitment.
Sub-model fitment matters on the 2004 Infiniti Q45 because the covered configurations do not share the same tire size or rim diameter. Choosing correctly starts with confirming whether the car is a Base model or a w/Premium Pkg. car, then matching the tire to the wheel already in place.
1
2004 Infiniti Q45 Base
The 2004 Infiniti Q45 Base uses the 225/55R17 radial fitment. That gives owners a choice between blackwall performance-oriented tires and more appearance-driven options such as wide whitewall or redline, while still keeping the correct 17-inch size in focus.
The 2004 Infiniti Q45 w/Premium Pkg. uses the 245/45R18 radial fitment. Tire selection here centers on confirming the 18-inch wheel setup first, then comparing blackwall options across the available BFGoodrich and Nitto performance-oriented series.
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 2004 Infiniti Q45 Tires for Sale
Available 2004 Infiniti Q45 tires cover both primary sizes, with BFGoodrich options in multiple g-Force series plus Silvertown Radial styling choices for 225/55R17, and BFGoodrich or Nitto blackwall selections for 245/45R18. The product grid is where sidewall treatment, tire series, rim-width compatibility, and load-related specs become the main comparison points.
Common 2004 Infiniti Q45 tire questions usually come down to identifying the correct sub-model, matching the wheel diameter, and then sorting through radial tire series, sidewall appearance, and road-use checks before putting the car back into service.
Tire Size & Fitment
What tire size fits a 2004 Infiniti Q45?
The 2004 Infiniti Q45 uses two different tire sizes depending on configuration. The Base model uses 225/55R17, while the 2004 Infiniti Q45 w/Premium Pkg. uses 245/45R18, and both are radial fitments tied to different wheel diameters.
That means the first step is not choosing a brand or tread style, but confirming which sub-model and wheel package the car actually has. A Q45 that has been fitted with different wheels over time should be checked carefully so the selected tire matches the current rim diameter and the intended setup.
What size rim does a 2004 Infiniti Q45 use?
A 2004 Infiniti Q45 uses either a 17-inch or 18-inch rim, depending on sub-model. The Base model uses the 225/55R17 fitment on a 17-inch rim, while the w/Premium Pkg. uses the 245/45R18 fitment on an 18-inch rim.
Wheel diameter is the key fitment checkpoint on this car because the two tire sizes are not meant for the same rim. Looking at the sidewall size already on the car and measuring the wheel if needed can prevent ordering a tire that matches the model year but not the actual wheel package installed.
Why does the 2004 Infiniti Q45 have more than one tire size?
The 2004 Infiniti Q45 has more than one tire size because the covered sub-models use different wheel and tire packages. The Base model uses 225/55R17, while the w/Premium Pkg. uses 245/45R18, so the variation is tied directly to the configuration of the car.
That difference affects more than just the sidewall marking. It changes the rim diameter you need to match and influences which product families are available, including appearance-oriented 17-inch options versus blackwall 18-inch performance-style choices. Confirming the exact package keeps the search centered on the tire size that belongs on that version of the Q45.
Choosing the Right Tire
What should I consider when choosing a tire for a 2004 Infiniti Q45?
Start with the correct primary size for the exact car: 225/55R17 for the Base model or 245/45R18 for the w/Premium Pkg. From there, compare radial construction details such as rim-width compatibility, sidewall style, tire series, and load-related specifications where they are stated.
The best choice depends on how the car is used and how it is meant to look. Some 17-inch options lean toward a traditional presentation with whitewall or redline styling, while others stay fully modern with blackwalls. For the 18-inch fitment, the comparison is mainly among blackwall performance-oriented product lines and their wheel compatibility ranges.
What sidewall styles are available for 2004 Infiniti Q45 tires?
Sidewall choices for the 2004 Infiniti Q45 vary by tire size. In 225/55R17, available styles include Blackwall, Wide Whitewall, and Redline, while the 245/45R18 fitment is represented here by Blackwall options.
That makes sidewall appearance an important part of the decision, especially for a Base model on 17-inch wheels. A blackwall keeps the look contemporary and understated, while a whitewall or redline creates a more personalized or restoration-inspired presentation. The right choice should still begin with the correct size and wheel diameter for the car.
What brands offer tires for the 2004 Infiniti Q45?
BFGoodrich offers tires in both primary 2004 Infiniti Q45 sizes, and Nitto appears in the 245/45R18 fitment. Within BFGoodrich, the available choices span several g-Force lines as well as Silvertown Radial options in the 17-inch size.
Brand choice is only one part of the selection process. It helps more to compare which brand offers the right combination of correct size, wheel compatibility, tire series character, and sidewall treatment for the exact Q45 configuration. That keeps the focus on usable fitment rather than treating all tires in the same nominal size as interchangeable.
Restoration & Appearance
Which tire should I choose for a period-style 2004 Infiniti Q45?
For a period-style 2004 Infiniti Q45, the strongest appearance-focused choices appear in the 225/55R17 Base-model fitment, where Silvertown Radial options are available alongside modern blackwall tires. That allows a more traditional visual treatment without leaving the correct primary size for the 17-inch setup.
The decision depends on whether the goal is a clean original-era luxury-sedan feel or a more customized presentation. A blackwall usually keeps the look closest to mainstream early-2000s luxury styling, while a wide whitewall or redline makes a stronger visual statement. Owners concerned with exact historical presentation should compare against marque-specific references before finalizing appearance details.
How does tire construction affect the appearance of a restored 2004 Infiniti Q45?
On the 2004 Infiniti Q45, construction is straightforward because the primary fitments are radial tires. The visual difference comes less from bias-ply-versus-radial questions and more from whether the chosen radial uses a blackwall, wide whitewall, or redline sidewall treatment in the 17-inch size.
That means restoration-oriented buyers should focus on size first and appearance second. A correct-size radial preserves the proper wheel relationship, while sidewall style shapes the final presentation of the car. For the 18-inch package, the available look remains blackwall and performance-oriented, so appearance variation is much narrower than it is with the 17-inch fitment.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2004 Infiniti Q45?
Yes, modifications can affect tire fitment on a 2004 Infiniti Q45, especially because the car already has two distinct factory-size paths tied to different wheel diameters. Aftermarket wheels, suspension changes, or altered ride height can all change the clearance relationship around a 225/55R17 or 245/45R18 tire.
A Q45 that has been lowered or fitted with non-original wheels should be checked for actual rim diameter, wheel width, and clearance at the fender and steering range before tire selection. That matters even when the sidewall size looks close, since the correct sub-model fitment and the current hardware on the car may no longer be the same thing.
What should I inspect before driving a 2004 Infiniti Q45 on new tires?
Before driving a 2004 Infiniti Q45 on new tires, inspect the wheels for damage, verify that the tire size matches the correct 17-inch or 18-inch setup, and check inflation, valve condition, and overall mounting quality. It also helps to confirm that the tires clear properly at full steering lock and through normal suspension movement.
A collector or low-use luxury sedan can also hide age-related issues that are not tire-specific, such as worn bushings, alignment problems, or uneven previous wear patterns. Taking a short, careful road test after installation gives a chance to catch vibration, pull, or clearance concerns before the car is returned to regular road use.
How often should tires on a 2004 Infiniti Q45 be inspected?
Tires on a 2004 Infiniti Q45 should be inspected regularly, even if the car is driven only occasionally. A visual check for cracking, bulges, cuts, irregular wear, and air loss should be part of routine ownership, and a closer inspection is worthwhile before longer drives or after seasonal storage.
Low-use cars can age tires out long before the tread looks worn, so condition matters as much as mileage. Pressure should be checked with the tires cold, and any Q45 that sits for extended periods benefits from clean storage away from prolonged sunlight, moisture, and ozone sources. Catching deterioration early helps protect both ride quality and fitment safety.
