Thinking about putting some bigger tyres on your Toyota Hilux? Wondering what the biggest legal tyre size is for your model?
Before you run out and buy some enormous tyres to put on your ute, it's worth brushing up on the legalities of increasing your tyre diameter from the stock size.
In most Australian states, the VSB 14 regulations dictate the legality of vehicle modifications.
As we know from these regulations, standard passenger vehicle tyre diameter can only be increased by 15mm from the diameter designated by the manufacturer for that model.
For 4WD passenger and goods vehicles designed for off-road use, that allowance increases to 50mm more than the diameter designated for that model (regardless of lift).
To calculate the maximum legal tyre size for your Hilux, select whether your vehicle is subject to 15mm or 50mm diameter restrictions, and enter the tyre size on the placard found on the driver's side door.
For your reference, here are some common Hilux models along with their manufacturer recommended size and legal maximum size. Note that this table assumes a maximum diameter increase of 50mm (as is standard for 4WDs).
|Max Legal Size
|2022 Hilux 2.8 D-4D - Diesel
|2021 Hilux 2.4 D-4D - Diesel
|2020 Hilux 2.7 VVT-i 2WD - Petrol
|2018 Hilux 4.0 VVT-i 4WD - Petrol
If you want to do the calculations yourself, here's how.
First, you'll need to calculate the diameter of the manufacturer recommended tyres for your vehicle. The diameter is the sum of the wheel/rim size plus 2 times the sidewall size (all in millimetres).
If your stock tyre size is 265/65R17, your sidewall size will be:
Sidewall size = 265mm x 0.65 = 172.25mm
Your wheel/rim size is simply the conversion of the 17 inches into millimetres:
Rim size = 17 inches x 25.4 mm/inch = 431.8mm
Therefore, your stock tyre diameter is:
Stock tyre diameter = (2 x 172.25mm) + 431.8mm = 776.3mm
If you have a 4WD Hilux, your maximum legal tyre diameter as per VSB 14 will be the stock diameter plus 50mm.
Max tyre diameter = 776.3mm + 50mm = 826.3mm
Now, you just need to find a tyre size with a diameter less than 826.3mm (but as close as possible).
I'm Louis, an engineer passionate about helping Australians choose better tyres for their vehicles!