The 2019 Lexus IS300 sits in the modern sport-sedan space where sharp handling, compact rear-drive proportions, and everyday usability all matter. Buyers looking at this generation often care as much about maintaining the car’s balanced road manners as they do preserving its clean, understated Lexus character. Tire fitment centers on radial sizes in 17-inch and 18-inch diameters, with some configurations using a square setup and others using a staggered front-and-rear combination. That opens the door to choices in brand, tire series, and sidewall presentation, including blackwall, raised white letter, and redline options in the 17-inch size. The right decision starts with confirming the exact wheel setup on the car.
Which Tire Size Is Right for The 2019 Lexus IS300
The 2019 Lexus IS300 uses three primary tire sizes, and the right one depends on the exact wheel and sub-model configuration. Some versions use a 225/45R17 radial on a 17-inch rim, while others use an 18-inch staggered setup with 225/40R18 in front and 255/35R18 in the rear. Before choosing a tire, confirm whether the car has 17-inch wheels or the 18-inch front-and-rear pairing.
225/45R17 is a metric radial size that uses a 225-millimeter section width, a 45-series aspect ratio, and a 17-inch rim diameter. On the 2019 Lexus IS300, this size suits square-fitment configurations where the same tire size is used at all four corners. Available choices include BFGoodrich, Nitto, and Pro-Trac, with sidewall treatments ranging from blackwall to raised white letter and redline, depending on the tire series. This size is the right starting point when the car carries 17-inch wheels and the goal is to match the existing wheel diameter without moving into the staggered 18-inch setup.
Fit(s): (AWD) Front, (RWD) Front, and F Sport Front
Construction: Radial|Rim: 18 in
225/40R18 is a metric radial size with a 225-millimeter section width, a 40-series profile, and an 18-inch rim diameter. On the 2019 Lexus IS300, it serves as the front tire in staggered 18-inch applications rather than a universal fitment for every configuration. Product choices in this size include BFGoodrich and Nitto across several performance-oriented series, all in blackwall styling. This is the size to evaluate when the car has 18-inch front wheels and needs the correct front fitment to match the corresponding rear tire size.
255/35R18 is a wider metric radial size that combines a 255-millimeter section width with a 35-series profile on an 18-inch rim. For the 2019 Lexus IS300, this size is used at the rear in staggered 18-inch setups, where it works with a narrower 225/40R18 front tire. BFGoodrich and Nitto offer options in several radial series, and the available products in this size are blackwall designs. This size should be chosen only after confirming the car uses the staggered 18-inch arrangement, since it is not the front tire size and does not apply to the 17-inch square setup.
Sub-model fitment on the 2019 Lexus IS300 matters because some versions use a single 17-inch tire size while others use an 18-inch staggered front-and-rear combination. Confirming the exact AWD, RWD, or F Sport wheel setup is the first step before comparing tire choices.
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2019 Lexus IS300 (AWD)
The 2019 Lexus IS300 (AWD) uses the 225/45R17 radial size in a square arrangement. That makes tire selection more straightforward, with the main decision shifting to brand, tire series, and sidewall treatment rather than front-to-rear size matching.
The 2019 Lexus IS300 (AWD) Front uses 225/40R18 as part of the 18-inch staggered setup. Tire selection here needs to stay coordinated with the matching rear size so the car keeps the intended front-and-rear wheel and tire relationship.
The 2019 Lexus IS300 (AWD) Rear uses the wider 255/35R18 radial size. That means rear tire choice should be made with the front 225/40R18 size in mind, especially when replacing tires in pairs or maintaining a staggered appearance.
The 2019 Lexus IS300 (RWD) also uses the 225/45R17 radial size in square form. With the same size at all four corners, the focus becomes choosing the right tire line and sidewall style for the way the car is driven and presented.
The 2019 Lexus IS300 (RWD) Front uses 225/40R18 when equipped with the 18-inch staggered arrangement. Selecting this front size correctly is important because it is part of a matched front-and-rear setup rather than a standalone all-around fitment.
The 2019 Lexus IS300 (RWD) Rear uses 255/35R18 on the back of staggered 18-inch cars. This rear size should be evaluated alongside the front tire and actual wheel dimensions so the staggered setup remains properly matched.
The 2019 Lexus IS300 F Sport Front uses the 225/40R18 radial size. Tire choice here is centered on selecting an 18-inch front tire that complements the wider rear fitment and suits the car’s existing wheel setup.
The 2019 Lexus IS300 F Sport Rear uses the 255/35R18 radial size at the back. That makes rear replacement a staggered-fitment decision, where wheel width and the corresponding front size should be checked before changing tire 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 2019 Lexus IS300 Tires for Sale
Available 2019 Lexus IS300 tire choices span 225/45R17, 225/40R18, and 255/35R18 radial sizes from BFGoodrich, Nitto, and Pro-Trac. Buyers can compare tire series, blackwall styling across all sizes, and added RWL or redline sidewall options in the 17-inch fitment.
These 2019 Lexus IS300 tire FAQs focus on exact size fitment, 17-inch versus 18-inch wheel setups, staggered front-and-rear applications, brand and sidewall choices, and the inspection points that matter before regular road use.
Tire Size & Fitment
What tire size fits a 2019 Lexus IS300?
The 2019 Lexus IS300 uses three primary tire sizes: 225/45R17, 225/40R18, and 255/35R18. The 225/45R17 size is used on 17-inch square setups, while 225/40R18 front and 255/35R18 rear are used on 18-inch staggered applications.
The practical step is confirming which wheel package is actually on the car before ordering tires. A 17-inch setup uses the same size all around, but the 18-inch arrangement requires matching the correct front and rear sizes to the existing wheel positions.
What size rim does a 2019 Lexus IS300 use?
The 2019 Lexus IS300 uses either a 17-inch or 18-inch rim, depending on the tire size and configuration. The 225/45R17 size fits a 17-inch rim, while both 225/40R18 and 255/35R18 are built for 18-inch rims.
Wheel diameter should be checked first because a 17-inch tire cannot be mounted on an 18-inch wheel, and vice versa. It also helps to confirm actual wheel width before comparing tire options, especially on staggered 18-inch setups or cars that may have changed wheels since new.
Why does the 2019 Lexus IS300 have more than one tire size?
The 2019 Lexus IS300 has more than one tire size because some configurations use a square 17-inch setup, while others use a staggered 18-inch arrangement with different front and rear sizes. That is why 225/45R17, 225/40R18, and 255/35R18 all appear for this model.
The key is identifying the exact sub-model and wheel package on the car. Once that is confirmed, tire selection becomes much easier because the buyer can focus on the correct size pattern, then compare construction details, tire series, sidewall style, and wheel-width compatibility within that fitment.
Choosing the Right Tire
What should I consider when choosing a tire for a 2019 Lexus IS300?
Start with the correct size and wheel configuration for the car: 225/45R17 for square 17-inch setups, or 225/40R18 front with 255/35R18 rear for staggered 18-inch applications. From there, compare radial tire series, sidewall style, and rim-width specifications where those details are available.
It also helps to think about how the IS300 is used. A car driven regularly may lead the owner toward one tire series, while a more appearance-focused setup may put more emphasis on sidewall treatment, especially in the 17-inch size where blackwall, RWL, and redline choices exist.
What sidewall styles are available for 2019 Lexus IS300 tires?
Sidewall options for the 2019 Lexus IS300 include blackwall across all three primary sizes, with added raised white letter and redline availability in 225/45R17. Those extra sidewall treatments appear in the 17-inch fitment rather than the 18-inch front and rear sizes.
That means sidewall choice depends partly on the wheel package already on the car. Owners keeping a 17-inch setup have more visual variety, while buyers with the staggered 18-inch arrangement will be comparing tire series and brand options within a blackwall presentation.
What brands offer tires for the 2019 Lexus IS300?
Tires for the 2019 Lexus IS300 are available from BFGoodrich, Nitto, and Pro-Trac, depending on the size. BFGoodrich appears across all three primary sizes, Nitto is available in each size as well, and Pro-Trac appears in the 225/45R17 fitment.
Brand is only one part of the decision. It is worth comparing the tire series each brand offers in the correct size, along with sidewall style, supported rim-width range, load figures where shown, and whether the car uses a square or staggered setup.
Restoration & Appearance
Which tire should I choose for a period-style 2019 Lexus IS300?
A period-style 2019 Lexus IS300 tire choice usually starts with keeping the car in its existing factory-era size format rather than changing wheel diameter or tire profile. That means 225/45R17 for 17-inch square setups, or 225/40R18 front with 255/35R18 rear for 18-inch staggered cars.
Appearance then comes down to the character of the tire series and sidewall style. Blackwall maintains the cleanest modern look across all sizes, while the 17-inch fitment adds RWL and redline choices for owners who want a more customized presentation without changing the base size.
How does tire construction affect the appearance of a restored 2019 Lexus IS300?
On the 2019 Lexus IS300, tire construction does not create a bias-ply-versus-radial appearance decision because the primary fitments are radial. The visual difference is more about profile, width relationship, wheel diameter, and sidewall treatment than about switching between vintage and modern construction types.
That makes size accuracy especially important for a clean, restoration-minded presentation. Keeping the correct 17-inch square or 18-inch staggered layout preserves the car’s intended stance more effectively than forcing an incorrect front-to-rear match or changing to a wheel diameter that alters the overall look.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2019 Lexus IS300?
Yes, modifications can affect tire fitment on a 2019 Lexus IS300 even when the tire size itself is correct. Aftermarket wheels, changes in wheel width, suspension lowering, or alignment changes can all influence how 225/45R17, 225/40R18, or 255/35R18 tires sit and clear the body.
A modified car should be checked for inner clearance, fender clearance, and front-to-rear size matching before a new set is installed. That matters most on staggered 18-inch setups, where front and rear tires serve different positions and wheel changes can alter the fitment margin quickly.
What should I inspect before driving a 2019 Lexus IS300 on new tires?
Before driving a 2019 Lexus IS300 on new tires, inspect tire pressure, bead seating, valve condition, wheel hardware, and overall clearance at full steering lock. It is also smart to confirm that the correct tire sizes are mounted in the proper positions, especially on staggered 18-inch setups.
A short initial road check can reveal vibration, rubbing, or other setup issues before they become larger problems. After the first miles, recheck inflation and look over the tread and sidewalls again so any mounting or clearance concern is caught early.
How often should tires on a 2019 Lexus IS300 be inspected?
Tires on a 2019 Lexus IS300 should be inspected regularly for pressure loss, uneven tread wear, cuts, bulges, and sidewall damage. On a car that is driven less often, periodic inspection still matters because age and storage conditions can affect tire condition even when tread mileage stays low.
Routine checks are especially useful on staggered setups because front and rear tires do different jobs and may show wear differently. Paying attention to condition, not just tread depth, helps preserve handling consistency and gives the owner time to address wheel, alignment, or suspension issues before they damage a new set.
