biggest legal tyres for hilux

Short answer: it depends on your state regs, but for many 4WD utes like the Hilux the common limit without certification is an increase of about +50 mm in overall tyre diameter. Go bigger than that and you’re into engineering approval/mod plate territory, plus potential issues with speedometer accuracy, ESC/ABS, and keeping the tread under the guards. Width changes also need to respect your rim specs and load rating, and tyres must meet or exceed the placard’s load and speed indices.

Practical tip: measure the actual rolling diameter of your target size, compare against placard, and have the speedo checked after fitting. Most folks land on sizes that are roughly +25 to +50 mm over stock for a safe, legal lift without drama. Always confirm with your state’s adoption of VSB 14/NCOP and your insurer—Consult official documentation for exact figures.