The 2018 Infiniti Q70 is a full-size luxury sedan from the final years of Infiniti’s traditional rear-drive sport-sedan formula, blending executive-car comfort with a distinctly driver-focused character. Buyers looking at this exact model are usually balancing appearance, wheel size, and intended road use as much as simple replacement fitment. Tire selection centers on two primary radial sizes, 245/50R18 and 245/40R20, with fitment varying by sub-model and wheel setup. Available choices also introduce sidewall personality, including blackwall, raised white letter, and redline treatments across several performance-oriented series. The important first step is confirming the exact sub-model and wheel diameter before comparing style and product differences.
Which Tire Size Is Right for The 2018 Infiniti Q70
The 2018 Infiniti Q70 uses two primary tire sizes, and the right one depends first on the exact sub-model and wheel diameter. Both sizes are radial constructions, but they are tied to different rim diameters, so confirming whether the car has 18-inch or 20-inch wheels is the key first step before comparing sidewall style, brand, or tire series.
A 245/50R18 tire is a metric radial size with a 245-millimeter section width, a 50-series aspect ratio, and fitment for an 18-inch rim. For the 2018 Infiniti Q70, this size serves the 18-inch wheel configuration and remains a modern radial fitment rather than a vintage-style sizing format. The available product choices center on Pro-Trac Street Pro III options, with both raised white letter and redline sidewall treatments available to change the car’s visual presentation. This size is the correct starting point when the vehicle has 18-inch wheels and the goal is matching that setup before comparing style details.
Sub-model fitment matters on the 2018 Infiniti Q70 because not every version uses the same wheel and tire combination. The 3.7 Luxe and 5.6 Luxe can use either of the two primary sizes, while the Hybrid stays with the 18-inch fitment, so identifying the exact model is important before selecting tires.
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2018 Infiniti Q70 3.7 Luxe
The 2018 Infiniti Q70 3.7 Luxe can use either of the two primary radial sizes, which means wheel diameter has to be confirmed on the car itself before moving further. Once that is settled, the choice shifts to tire series, brand, and sidewall appearance within the correct size.
The 2018 Infiniti Q70 5.6 Luxe also spans both primary radial fitments, so this sub-model is another case where wheel size verification comes first. Tire selection then becomes a matter of matching the installed 18-inch or 20-inch setup and comparing the available product styles.
The 2018 Infiniti Q70 Hybrid uses the 18-inch radial fitment rather than sharing both wheel-size combinations seen elsewhere in the lineup. That makes the tire decision more straightforward, with attention focused on choosing the right 245/50R18 product and preferred sidewall treatment.
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 2018 Infiniti Q70 Tires for Sale
Available 2018 Infiniti Q70 tires span 18-inch and 20-inch radial fitments, with brands including BFGoodrich, Nitto, and Pro-Trac. Buyers can compare tire series such as g-Force Comp 2 AS, g-Force Phenom T/A, NT555 G2, and Street Pro III, along with blackwall, raised white letter, and redline sidewall styles.
These FAQs focus on the exact tire sizes used on the 2018 Infiniti Q70, how sub-model and wheel diameter affect fitment, and how to compare available radial tire options, sidewall styles, and road-use checks.
Tire Size & Fitment
What tire size fits a 2018 Infiniti Q70?
The 2018 Infiniti Q70 uses two primary tire sizes: 245/50R18 and 245/40R20. Both are radial sizes, but they do not apply the same way across the lineup. The 3.7 Luxe and 5.6 Luxe can use either size, while the Hybrid uses 245/50R18.
The practical first step is confirming the exact sub-model and checking whether the car has 18-inch or 20-inch wheels. Since both sizes use the same nominal width but different profiles and rim diameters, selecting by appearance alone can lead to the wrong fitment. Matching the installed wheel setup matters before comparing tire brands or sidewall treatments.
What size rim does a 2018 Infiniti Q70 use?
A 2018 Infiniti Q70 uses either an 18-inch or 20-inch rim, depending on the tire size and sub-model setup. The 245/50R18 tire fits an 18-inch rim, while the 245/40R20 tire fits a 20-inch rim. Both rim diameters are part of the normal fitment range for this model year.
Checking the actual wheel on the car is especially important on the 3.7 Luxe and 5.6 Luxe because both sizes can apply there. A quick sidewall check will usually confirm the installed size, and that should match the wheel diameter. Once rim diameter is verified, the tire search becomes much narrower and more accurate.
Do all 2018 Infiniti Q70 sub-models use the same tire size?
No, not all 2018 Infiniti Q70 sub-models use the same tire size in the same way. The 3.7 Luxe and 5.6 Luxe can use 245/50R18 or 245/40R20, while the Hybrid uses 245/50R18. That means the Q70 lineup is not a one-size-fits-all tire application.
This matters because two cars that both say Q70 on the trunk may still need different tires depending on their wheel package. Identifying the exact sub-model helps, but the final check should still be the tire size already mounted on the vehicle. That approach reduces mistakes when comparing available series, sidewall styles, and replacement options.
Choosing the Right Tire
What should I consider when choosing a tire for a 2018 Infiniti Q70?
Start with the correct size for the car’s current wheel setup: 245/50R18 for 18-inch rims or 245/40R20 for 20-inch rims. Both are radial fitments, so the main decision is not bias-ply versus radial, but rather matching wheel diameter first and then comparing the available tire lines within that size.
After size is confirmed, focus on the differences that affect how the car looks and how the tire is built. Brand, tire series, sidewall treatment, rim-width compatibility, and load-related specifications can all shape the decision. A Q70 used as a clean luxury sedan may call for a different presentation than one being styled with redlines or raised white letters.
What sidewall styles are available for 2018 Infiniti Q70 tires?
Sidewall choices for the 2018 Infiniti Q70 include blackwall, raised white letter, and redline, depending on the tire size and product line. Blackwall appears in the 20-inch fitment from BFGoodrich and Nitto, while Pro-Trac Street Pro III brings raised white letter and redline options in both 18-inch and 20-inch sizes.
That variety gives the Q70 owner some visual flexibility beyond a plain replacement tire. Blackwall suits a restrained modern look, while raised white letter and redline options create a more stylized presentation. The right choice still begins with the correct size and wheel diameter, then moves to the sidewall treatment that best fits the car’s overall look.
What brands offer tires for the 2018 Infiniti Q70?
Available tire brands for the 2018 Infiniti Q70 include BFGoodrich, Nitto, and Pro-Trac. The 20-inch fitment has the widest brand spread, with BFGoodrich and Nitto blackwall offerings alongside Pro-Trac Street Pro III choices. The 18-inch fitment centers on Pro-Trac options with different sidewall styles.
Brand selection matters most after the correct size has been narrowed down. Some buyers will be comparing a more conventional blackwall performance presentation, while others will be choosing between raised white letter and redline styling. Looking at brand together with series and sidewall style helps separate appearance-driven choices from straightforward replacement needs.
Restoration & Appearance
Which tire should I choose for a period-style 2018 Infiniti Q70?
A period-style approach on a 2018 Infiniti Q70 usually starts with keeping the correct installed wheel diameter and matching the proper tire size, either 245/50R18 or 245/40R20. Since this is a modern luxury sedan with radial fitments, the appearance decision tends to come from sidewall treatment and tire series rather than vintage construction changes.
For a cleaner contemporary presentation, blackwall options suit the Q70’s original era well. If the goal is a more stylized enthusiast look, redline or raised white letter choices can change the car’s personality without changing its basic tire format. The best result comes from balancing appearance with the actual wheel setup already on the car.
How does tire construction affect the appearance of a restored 2018 Infiniti Q70?
On a 2018 Infiniti Q70, tire construction is straightforward because the primary fitments are radial. That means appearance differences are driven less by bias-ply versus radial concerns and more by the sidewall and series choices within the correct radial size. Blackwall, redline, and raised white letter options can all change the car’s visual tone.
A blackwall tire keeps the look restrained and closer to what many buyers expect from a late-model luxury sedan. Redline and raised white letter treatments add a custom or enthusiast-oriented edge that may suit some builds better than others. Keeping the right size and rim diameter in place is still the foundation for any appearance-focused decision.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2018 Infiniti Q70?
Yes, modifications can affect tire fitment on a 2018 Infiniti Q70 even when the tire size itself is one of the normal applications for the model. Aftermarket wheels, changes in wheel width, altered offset, suspension lowering, or body modifications can all change how a 245/50R18 or 245/40R20 tire sits in the car.
A Q70 with non-original wheels should be checked for more than rim diameter alone. Steering clearance, fender room, and the relationship between tire width and wheel width all matter once the factory setup changes. That is especially important on the sub-models that can use either 18-inch or 20-inch fitments, because wheel swaps are easier to assume than to verify.
What should I inspect before driving a 2018 Infiniti Q70 on new tires?
Before driving a 2018 Infiniti Q70 on new tires, inspect the installed wheel diameter, confirm the tire size matches the car’s setup, and check overall tire condition after mounting. It is also smart to look for proper air pressure, bead seating, valve-stem condition, and any obvious interference around the wheelwell or suspension area.
A short, careful road test helps confirm that the tires track cleanly and clear properly during turning and normal suspension movement. Any vibration, rubbing, or uneven stance should be addressed before regular use. On a car that may have seen wheel changes over time, that first inspection is often what separates a correct installation from a frustrating one.
How often should tires on a 2018 Infiniti Q70 be inspected?
Tires on a 2018 Infiniti Q70 should be inspected regularly, not just when tread looks worn. Frequent checks for pressure loss, cuts, bulges, uneven wear, and sidewall damage are important on both 245/50R18 and 245/40R20 fitments. A modern luxury sedan can mask tire issues well, so visual checks should be routine rather than occasional.
Cars that are driven less often still need attention because age, storage conditions, and long periods of sitting can affect tire condition. Checking before longer drives is especially worthwhile, particularly if the Q70 is a second vehicle or spends time parked. Consistent inspection helps catch problems early and protects the ride quality expected from this platform.
