Mud Tires for a Toyota 4Runner

Start with what Toyota fits

Toyota’s 2026 4Runner specifications list three tire sizes. The SR5 gets 245/70R17. The Limited gets 265/55R20. The TRD Off-Road gets a 265/70R18 all-terrain, and the TRD Pro and Trailhunter get the same size as a Toyo Open Country A/T III. None of them is a mud-terrain, and none is an LT tire.

Worked out from the sidewall numbers, 245/70R17 is about 30.5 inches tall, 265/55R20 about 31.5 and 265/70R18 about 32.6. Toyota calls the 18-inch tire a 33-inch tire; by the numbers it is 32.6.

Standard tires from toyota.com’s 2026 4Runner Full Specs, read 30 September 2026. Heights are calculated from the size, not measured. Other 2026 trims (TRD Sport, Platinum and the Premium packages) are not shown here.

The load range question, in numbers

Toyota lists a GVWR of 6,005 lb for a two-wheel-drive SR5 and 6,505 lb for the TRD Off-Road i-FORCE MAX, TRD Pro and Trailhunter. At 6,505 lb that is about 1,626 lb per corner.

The TRD Pro’s Toyo Open Country A/T III in 265/70R18 is a 116T Standard Load tire rated 2,756 lb on tiresize’s figures. A P-metric tire on a light truck or SUV has its rating divided by 1.10, which leaves 2,505 lb per tire and 10,022 lb across four: about 54% more than the heaviest 4Runner is allowed to weigh.

That is a comfortable margin, but not a huge one. A Load Range E mud-terrain in LT285/65R18 is rated 3,640 lb at 80 psi: 14,560 lb across four, 2.24 times that GVWR. Toyota rates the 4Runner to tow 6,000 lb (5,800 lb for the TRD Pro and Trailhunter). If you tow near that, the extra casing is capacity you will use; if you do not, it mostly buys stiffness. In the 4Runner sizes below, almost every mud-terrain is Load Range E anyway.

The weight penalty

The factory Toyo is light: 44 lb in 265/70R18 on tiresize’s figures. A mud-terrain in LT285/65R18, the closest height match, weighs 62.0 lb (Maxxis RAZR MT) to 67.3 lb (Nitto Trail Grappler): 18 to 23 lb more per corner, roughly 72 to 93 lb of extra unsprung, rotating mass across the truck. On a TRD Off-Road, TRD Pro or Trailhunter, which Toyota lists at 5,225 to 5,500 lb with a four-cylinder hybrid, you will feel that in braking and acceleration. Our fuel economy guide covers how it shows up at the pump.

What fits without a lift

Toyota publishes no maximum tire size, so we will not invent one. What the numbers do show: LT285/65R18 measures 32.6 to 32.8 inches in the six mud-terrains we track, within about 0.2 inch of the factory 265/70R18. It is about 0.8 inch wider, so check your wheel’s width and offset, but it barely changes the height or the speedometer.

On a 17-inch SR5 the gap is bigger. LT285/70R17 measures 32.8 to 33.15 inches, 2.3 to 2.65 inches taller than the factory 30.5, which is lift territory.

What a lift actually buys

ReadyLIFT publishes a tire size for each 4Runner kit, which makes its claims checkable. For the 2025-on 4Runner, its 2.5-inch SST kit states 285/75R17 on a 17×8, +35 mm wheel, or 285/65R18 on an 18×9, +1 mm wheel with trimming. Its 3-inch SST kit states up to 285/75R17 on an 8-inch, +35 mm wheel or 295/55R20 on an 8.5-inch, +35 mm wheel without trimming, and 315/70R17 or 35×12.50R17 with minor trimming; the TRD skid plate does not work with it. Neither kit is for the TRD Pro or Trailhunter.

For the 2010–2024 4Runner, ReadyLIFT’s 2.5-inch SST2.1 system states a 33-inch maximum tire diameter, with 285/65R18 on an 18-inch, +0 offset wheel. It will not work on the TRD Pro or on trucks with X-REAS or KDSS suspension. Check the kit page for your exact truck before you buy anything.

Gearing and the speedometer

Every 2026 4Runner we checked uses an 8-speed automatic and a 3.58 final drive ratio. LT285/65R18 on an 18-inch truck changes the speedometer by less than 1%. On an SR5, going from 30.5 inches to LT285/70R17 at 32.8 to 33.15 inches is 7.5 to 8.7% taller, and 285/75R17 at about 33.8 inches is roughly 11% taller: the speedometer reads low by the same share, and the 3.58 axle behaves like a noticeably taller one. Our tire size calculator does this arithmetic for any size pair.

What is actually made in 4Runner sizes

Of the six mud-terrains we track (BFGoodrich KM3, Nitto Trail Grappler, Toyo Open Country M/T, Falken Wildpeak M/T, Maxxis RAZR MT and Milestar Patagonia M/T-02), these are the sizes that suit a 4Runner:

Tire Size (tiresize.com) model specification pages, as collected in our specification dataset. Load is the single-tire rating for the Load Range E version.

A 35×12.50R17 is only in play on a lifted 2025-on truck with trimming, per ReadyLIFT’s 3-inch kit. At 74 to 80 lb it adds roughly 30 to 36 lb per corner over the factory Toyo.

What we would buy

On a TRD Off-Road, TRD Pro or Trailhunter: LT285/65R18, in whichever of the six is cheapest that week (the price tracker has dated prices). It matches the factory height within about 0.2 inch, so the speedometer stays honest, and it carries 3,640 lb a tire in Load Range E.

Wanting more height on 18s: LT275/70R18, at about 33.4 inches, is taller than any 18-inch size ReadyLIFT states for these kits, so we would not fit it without the kit maker’s say-so.

On a lifted SR5 on 17s: LT285/70R17 at about 33 inches, within the 285/75R17 ReadyLIFT states for its 2.5-inch kit on a 2025-on truck.