The 2018 Lexus IS350 sits in the modern sport sedan category, blending Lexus refinement with a chassis and powertrain setup that rewards drivers who still care about steering feel and balanced road manners. Tire selection matters here because this car can appear in both a square 17-inch setup and a staggered 18-inch arrangement, depending on configuration. The primary fitments are radial sizes 225/45R17, 225/40R18 front, and 255/35R18 rear. Available choices also vary by brand, tire series, and sidewall treatment, especially in the 17-inch size. The right decision starts with confirming whether the car has the standard wheel package or the staggered setup before comparing tire options.
Which Tire Size Is Right for The 2018 Lexus IS350
Three tire sizes apply to the 2018 Lexus IS350, and the correct choice depends first on the car's wheel setup. Some configurations use a single 225/45R17 size on 17-inch rims, while others use a staggered 18-inch arrangement with 225/40R18 in front and 255/35R18 in the rear. Before selecting a tire, confirm both the sub-model and the actual rim diameter on the car.
In 225/45R17, the 225 identifies nominal section width in millimeters, 45 is the aspect ratio, R indicates radial construction, and 17 is the wheel diameter in inches. On the 2018 Lexus IS350, this size is used on the 17-inch wheel setup and keeps fitment straightforward because the same size is used at all four corners. Available choices include BFGoodrich, Nitto, and Pro-Trac, with blackwall, raised white letter, and redline sidewall treatments. This size makes sense for owners confirming a square setup and then narrowing the choice by appearance, series, and rim-width compatibility.
Fit(s): (AWD) Front, (RWD) Front, and F Sport Front
Construction: Radial|Rim: 18 in
In 225/40R18, the tire is 225 millimeters wide, uses a 40-series profile, radial construction, and fits an 18-inch rim. On the 2018 Lexus IS350, this size serves the front position in the staggered 18-inch setup rather than every configuration. Product choices in this size come from BFGoodrich and Nitto, primarily in blackwall performance-oriented series such as g-Force Comp 2 AS, g-Force Sport Comp 2, g-Force Phenom T/A, and NT555 G2. This is the size to evaluate when the car has 18-inch front wheels and the rear uses a different tire width.
In 255/35R18, the 255 designates a wider section width in millimeters, 35 is the lower-profile aspect ratio, R means radial, and 18 is the rim diameter. On the 2018 Lexus IS350, this size is used at the rear on staggered 18-inch configurations, pairing with a narrower 225/40R18 front tire. Available options include BFGoodrich and Nitto blackwall tires across several performance-focused series. This rear size should be chosen only after confirming the car uses the staggered arrangement and that the wheel width matches the tire's intended mounting range.
Sub-model fitment on the 2018 Lexus IS350 is split between a square 17-inch setup and a staggered 18-inch front-and-rear arrangement. Checking the exact configuration matters because the standard four-corner size and the staggered sizes are not selected the same way.
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2018 Lexus IS350 (AWD)
The 2018 Lexus IS350 AWD uses the 225/45R17 radial size in its non-staggered form. That keeps tire selection simpler, since the main decision becomes choosing the right brand, series, and sidewall style for a 17-inch square setup.
The 2018 Lexus IS350 AWD Front position uses 225/40R18 in the staggered 18-inch arrangement. Front tire selection should stay focused on the proper 18-inch size while also matching the overall setup being used at the rear.
The 2018 Lexus IS350 AWD Rear position uses 255/35R18 as part of the staggered 18-inch setup. Rear tire choice should account for the wider fitment and confirm that the wheel width and front-to-rear pairing remain consistent.
The 2018 Lexus IS350 RWD also appears with the 225/45R17 radial size in a square arrangement. For this configuration, the practical choice is less about front-versus-rear sizing and more about selecting the right tire series and appearance.
The 2018 Lexus IS350 RWD Front position uses 225/40R18 when equipped with the staggered 18-inch setup. Tire selection here should start with confirming the car is actually using the staggered package rather than the 17-inch square configuration.
The 2018 Lexus IS350 RWD Rear position uses 255/35R18 in the staggered 18-inch configuration. That means rear fitment should be chosen with the matching front size in mind, rather than treating the rear tire as a standalone replacement.
The 2018 Lexus IS350 F Sport Front uses 225/40R18 radial tires. Since this is the front half of a staggered setup, the right selection depends on maintaining the intended front size while coordinating properly with the rear fitment.
The 2018 Lexus IS350 F Sport Rear uses 255/35R18 radial tires. The wider rear fitment is a key part of the staggered arrangement, so wheel width and proper pairing with the front tire should be confirmed before replacement.
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 Lexus IS350 Tires for Sale
Available 2018 Lexus IS350 tire choices center on radial performance-oriented options from BFGoodrich, Nitto, and Pro-Trac. Depending on size, buyers can compare tire series such as g-Force Comp 2 AS, g-Force Sport Comp 2, g-Force Phenom T/A, NT555 G2, and Street Pro III, with blackwall, RWL, and redline sidewall treatments.
These FAQs focus on the tire sizes used on the 2018 Lexus IS350, how the 17-inch and staggered 18-inch setups differ, and what to check when comparing tire series, sidewall styles, wheel fitment, and road-use readiness.
Tire Size & Fitment
What tire size fits a 2018 Lexus IS350?
The 2018 Lexus IS350 uses three applicable tire sizes: 225/45R17, 225/40R18, and 255/35R18. The 225/45R17 size is used on the 17-inch square setup, while the 18-inch configuration uses a staggered arrangement with 225/40R18 in front and 255/35R18 in the rear.
The key is identifying which wheel package is actually on the car before replacing anything. A square 17-inch setup is selected differently than a staggered 18-inch setup, and mixing those fitments without checking wheel diameter and front-to-rear sizing can create avoidable problems.
What size rim does a 2018 Lexus IS350 use?
The 2018 Lexus IS350 uses either 17-inch or 18-inch rims, depending on configuration. The 225/45R17 tire fits a 17-inch rim, while the staggered setup uses 18-inch rims with 225/40R18 front tires and 255/35R18 rear tires.
Start by reading the tire sidewall and confirming the actual wheels on the car, especially if it was purchased used. Tire selection should follow the rim diameter already in place, and wheel width should also be checked when comparing among available performance-oriented tire options.
Why does the 2018 Lexus IS350 have more than one tire size?
More than one tire size applies because the 2018 Lexus IS350 was offered with different wheel and tire arrangements. Some versions use a square 225/45R17 setup, while others use a staggered 18-inch combination with a narrower 225/40R18 front tire and a wider 255/35R18 rear tire.
That means the correct tire is tied to the exact configuration rather than the model name alone. Checking whether the car has matching-size tires at all four corners or a front-and-rear staggered layout will prevent ordering a size that only belongs on one axle.
Choosing the Right Tire
What should I consider when choosing a 2018 Lexus IS350 tire?
Start with the correct size and wheel setup, because the 2018 Lexus IS350 may use 225/45R17 on all four corners or a staggered 18-inch setup with 225/40R18 front and 255/35R18 rear. Every applicable tire here is a radial, so the remaining choices center on series, sidewall style, and wheel compatibility.
After confirming size, compare the tire's intended character with how the car is driven and presented. A square 17-inch setup gives more room for appearance choices such as blackwall, RWL, or redline, while the 18-inch fitments are more narrowly focused on blackwall performance-style options.
What sidewall styles are available for 2018 Lexus IS350 tires?
Sidewall choices for the 2018 Lexus IS350 vary by size. The 225/45R17 size is available in blackwall, RWL, and redline styles, while the 225/40R18 and 255/35R18 sizes shown here are offered in blackwall form.
That gives the 17-inch setup more visual flexibility if appearance matters as much as fitment. Owners using the staggered 18-inch arrangement will usually be choosing among tire series and brand differences rather than sidewall styling, so the right comparison point shifts with the wheel package.
What brands offer tires for the 2018 Lexus IS350?
Tires for the 2018 Lexus IS350 are available from BFGoodrich, Nitto, and Pro-Trac, depending on size. BFGoodrich appears across all three fitments, Nitto is offered in each of the main sizes, and Pro-Trac is represented in the 225/45R17 size.
Brand should be compared alongside tire series, sidewall treatment, and wheel-width compatibility rather than in isolation. The 17-inch size offers the broadest visual variety, while the 18-inch front and rear sizes stay more tightly centered on blackwall radial performance-style selections.
Restoration & Appearance
Which tire should I choose for a period-style 2018 Lexus IS350?
A period-style approach on a 2018 Lexus IS350 usually means preserving the tire size and wheel presentation that suits the car's original-era appearance rather than changing the overall look. That starts with keeping either the square 225/45R17 setup or the staggered 18-inch arrangement the car already uses correctly.
Appearance choice then comes down to how much visual emphasis you want from the sidewall. The 17-inch size offers blackwall, raised white letter, and redline options, while the 18-inch fitments stay focused on blackwall tires, giving the car a more restrained modern sport-sedan presentation.
How does tire construction affect the appearance of a restored 2018 Lexus IS350?
For the 2018 Lexus IS350, construction is straightforward because the primary fitments are radial tires. The visual difference is less about bias-ply versus radial and more about maintaining the correct modern tire proportions, matching front and rear sizes on staggered cars, and choosing the sidewall treatment that suits the look.
Keeping the correct profile and wheel diameter matters because this generation depends on a low-profile, modern sport-sedan stance. A mismatched size or axle pairing can change the appearance quickly, even before any handling differences are noticed, so visual accuracy begins with correct fitment basics.
Fitment, Maintenance & Road Use
Can modifications affect tire fitment on a 2018 Lexus IS350?
Yes. Modifications such as aftermarket wheels, altered wheel width, offset changes, lowering springs, or suspension changes can affect tire fitment on a 2018 Lexus IS350 even when the tire size itself looks close to stock. That matters even more on cars using the staggered 18-inch front-and-rear setup.
A modified car should be checked for steering clearance, inner-fender space, and how the tire sits on the wheel actually installed. Verifying the wheel diameter and width before purchase is especially important when replacing only one axle on a staggered setup or when the car's stance has been changed.
What should I inspect before driving a 2018 Lexus IS350 on new tires?
Before putting a 2018 Lexus IS350 into regular road use on new tires, inspect wheel condition, confirm the correct size is mounted at each position, and check inflation, tread seating, and any visible signs of rubbing. On staggered cars, make sure the front and rear sizes have not been swapped.
It also helps to look over the suspension and alignment condition so the new tires are not being asked to compensate for unrelated wear. A short initial drive followed by a pressure check and visual reinspection is a sensible step, especially after mounting low-profile 18-inch fitments.
How often should tires on a 2018 Lexus IS350 be inspected?
Tires on a 2018 Lexus IS350 should be inspected regularly, not just when tread appears low. Routine checks should include pressure, uneven wear, cuts, punctures, sidewall damage, and any signs that the front and rear tires on a staggered setup are wearing differently than expected.
More frequent inspection makes sense if the car is driven spiritedly, stored for stretches, or has aftermarket wheel and suspension changes. Catching wear patterns early helps protect both ride quality and tire life, and it can also reveal alignment or clearance issues before they become expensive.
