Infiniti Q70 Tires

Infiniti Q70 models from 2014 through 2019 use two tire sizes: 245/50R18 on 18-inch wheels and 245/40R20 on 20-inch wheels. Both are radial metric sizes, and both appear across the full production span rather than being tied to early or late years only. That means the year alone does not identify the correct tire size on an Infiniti Q70.

The practical step is to match the tire size to the wheel diameter actually on the car. An Infiniti Q70 with 18-inch wheels takes 245/50R18, while an Infiniti Q70 with 20-inch wheels takes 245/40R20. Check the current tire sidewall, measure the wheel if needed, and verify that the car has not been changed from its original wheel package before choosing a replacement.

On an Infiniti Q70, 245/40R20 means the tire is 245 millimeters wide, has a 40-series aspect ratio, uses radial construction, and fits a 20-inch wheel. The lower 40-series profile gives this size a shorter sidewall than the 18-inch fitment. That construction and sizing place it firmly in the modern performance-oriented touring category rather than a vintage numeric or alphanumeric format.

The main implication is that a 245/40R20 tire cannot substitute for an 18-inch-wheel Infiniti Q70 even though the section width is the same. The wheel diameter and sidewall height are different, so ride, appearance, and fit are tied to the wheel package. If your Infiniti Q70 wears 20-inch wheels, stay with 245/40R20 unless you are making a deliberate wheel-and-tire package change.

Infiniti Q70 uses either an 18-inch or a 20-inch rim diameter across the 2014 to 2019 production run. The 245/50R18 fitment belongs to 18-inch wheels, and the 245/40R20 fitment belongs to 20-inch wheels. There is no year break where one diameter replaced the other, because both wheel diameters were used throughout the same years.

That makes wheel verification more important than model year when replacing tires on an Infiniti Q70. Look at the current tire sidewall or confirm the wheel diameter directly before choosing a size. This is especially important on used cars, because wheel packages may have been swapped, upgraded, or carried over from another trim appearance package during the car’s life.

The correct tire size for a 2014-2019 Infiniti Q70 is determined by wheel diameter first. An Infiniti Q70 with 18-inch wheels uses 245/50R18, and an Infiniti Q70 with 20-inch wheels uses 245/40R20. Since both sizes were used in every model year from 2014 through 2019, the model year by itself is not enough to choose a tire.

Start with the tire already fitted to the car, then confirm that it matches the wheel diameter and overall setup you intend to keep. If the car has been modified, compare the current wheel and tire package to service records or factory-style equipment references for that exact configuration. That extra check helps avoid ordering a tire that matches the year but not the actual wheel package on the car.

Available Infiniti Q70 tires include blackwall, RWL, and redline sidewall styles. Blackwall appears in several 245/40R20 options, while RWL and redline versions are offered in both 245/40R20 and 245/50R18. Those sidewall treatments do not change the basic size requirement, but they do change the visual character of the finished car.

A blackwall is the most understated choice for an Infiniti Q70 and keeps the look closest to a contemporary luxury sedan presentation. RWL or redline tires give the car a more custom or enthusiast-oriented appearance, which may appeal if the car has aftermarket wheels or a more personalized style direction. Choose the sidewall style after confirming the correct size and wheel diameter, not before.

Infiniti Q70 tire options here come from BFGoodrich, Nitto, and Pro-Trac. BFGoodrich and Nitto appear in the 245/40R20 fitment, while Pro-Trac offers both 245/40R20 and 245/50R18 products. All listed products for Infiniti Q70 are radial construction, so the brand choice is mainly about available series and sidewall presentation rather than switching between construction types.

That means your brand decision should come after you have identified whether your Infiniti Q70 uses 18-inch or 20-inch wheels. Once the size is settled, you can compare the available product lines and sidewall styles within that fitment. On a modern luxury sedan like the Infiniti Q70, keeping the tire size correct is more important to drivability and appearance than choosing a particular brand name first.

An Infiniti Q70 should be stored on a clean, dry surface away from direct sunlight, electric motors, welders, battery chargers, and other ozone sources that can age rubber. Keep the tires inflated to the vehicle’s normal storage pressure target and avoid letting the car sit for long periods with visibly underinflated tires. Clean the tires with mild soap and water rather than petroleum-based dressings.

If the Infiniti Q70 will sit for months, move it periodically to prevent flat spotting and keep one section of the tread from carrying the load continuously. A climate-stable garage is far better than outdoor storage, especially on larger low-profile fitments such as 245/40R20. If long-term storage is expected, supporting the vehicle properly and checking pressures on a schedule will help preserve both ride quality and casing shape.

Tires on an Infiniti Q70 should be inspected regularly even if the car is driven only occasionally. Check air pressure, tread wear pattern, sidewall cracking, punctures, impact damage, and any signs of uneven shoulder wear at least monthly and before any highway trip. A large luxury sedan places real load on its tires, so condition matters as much as tread depth.

A useful routine is to inspect the Infiniti Q70 every time it is washed or taken out after storage. Uneven wear can point to alignment issues, suspension wear, or incorrect inflation, all of which can affect how the car tracks and rides. Catching those issues early is especially helpful on 20-inch fitments, where shorter sidewalls can make damage and pressure sensitivity more noticeable.

An Infiniti Q70 tire should be replaced when it shows age cracking, sidewall damage, repeated air loss, vibration from casing issues, impact bruising, or irregular wear that cannot be corrected. Tread depth alone is not the only measure of serviceability on a collector-kept or low-mileage sedan. Tires can age out before they wear out, particularly on vehicles that spend long periods parked.

The practical approach is to treat age, condition, and driving plans together rather than waiting for the tread to look worn. A car that sees occasional local use may reveal aging through stiffness or surface cracking long before the grooves disappear. Have the Infiniti Q70 tires evaluated whenever the car has been stored extensively, driven on underinflated tires, or exposed to pothole or curb impacts.

The listed Infiniti Q70 tires are modern radial road tires in the two correct fitment sizes, so they are intended for normal public-road use when matched to the proper wheel diameter and kept in sound condition. Safety still depends on the individual tire’s age, inflation, wear state, and any damage history. The correct size alone does not make an Infiniti Q70 road-ready.

Before regular driving, make sure the Infiniti Q70 has a matched set in the proper size for its wheels, with no visible structural damage and no unresolved vibration or pull. A thorough alignment and pressure check are worthwhile if the car is newly acquired or has been sitting. On a heavier luxury sedan, correct maintenance has a direct effect on braking feel, steering response, and highway stability.

Before driving an Infiniti Q70, check tire pressure, sidewall condition, tread condition, and whether all four tires match the wheel diameter fitted to the car. Also look for bulges, embedded objects, curb damage, and any signs that the tire has been run low on air. If the car has 20-inch wheels, pay especially close attention to sidewall impacts because the shorter profile leaves less visual margin.

A short walk-around before each drive can prevent most tire-related surprises. If the Infiniti Q70 has been parked for an extended period, the first outing should include a slow-speed check for vibration, flat spotting, or pull before heading onto faster roads. That habit is particularly valuable on cars that alternate between storage and occasional use rather than seeing steady weekly mileage.

An Infiniti Q70 should be driven at speeds appropriate to the specific tire fitted, its inflation state, and its overall condition. The listed products are modern radial tires intended for contemporary road use, but safe speed is never just a matter of the size stamped on the sidewall. Tire age, damage, heat buildup, and load all matter on a full-size luxury sedan like the Infiniti Q70.

The sensible practice is to avoid sustained high-speed driving unless the Infiniti Q70 tires are in excellent condition, correctly inflated, and recently inspected. If the car is newly purchased or has spent long periods off the road, begin with moderate driving and evaluate ride quality, balance, and temperature after a short run. Building confidence gradually is wiser than assuming any older fitted tire is ready for maximum-speed use.