Originally Posted by
stevemc181
Pretty sure you can have up to a 50mm increase in tyre diameter on a 4wd over what the placard says.
The below is copied from the national code of practice and WA follows this as far as I am aware?
I also sometimes regret going up a tyre size, the small increase in clearance really isn't worth the loss of power and fuel economy.
The overall diameter of any tyre fitted to:
4WD passenger vehicles specifically designed for off-road use (typically MC ADR
category). All wheel drive (AWD) vehicles including those AWD vehicles that may be
certified as MC ADR category, (also commonly known as soft roaders) are not
included in this category;
4WD goods vehicles and their 2WD equivalents if the chassis and running gear are
essentially the same as the 4WD version (N ADR category); or
any medium weight goods vehicle (NA2, NB ADR category).
Must not be more than 50mm larger or 26mm smaller than that of any tyre designated by the
vehicle manufacturer for that vehicle.
Note: Increases in tyre diameter are subject to compliance with all other requirements
specified under this clause (Clause 4.2 Non-Standard Tyres and Rims) and may
therefore be limited by other factors such as insufficient clearance.