Thread: Only 15mm bigger?

It is the same in NSW .. if you exceed the rolling diameter of the standard tyre size recommended by the manufacturer by 15mm, it will render the vehicle unroadworthy. I'm not sure if you can get around it by getting an engineers certificate but that will mean $$$ on your part.

Many 4WD's on the road are unroadworthy, especially the guys running 33" and over. The good thing is .. this law is not enforced at all, unless you get a copper who really knows the laws .. or an insurance company that looks for ways not to pay out on a claim. Essentially a lift kit over 2 inches are also deemed unroadworthy but same thing applies .. they don't have the systems or knowledge in place to police it.

The legal way to solve it is with an engineers certificate. Otherwise you can't put them on.

Thanks guys

I guess that I will be sticking with standard & taking the chicken track on odd occasions. It would have been nice to have the added ground clearance where the big wheeled road pressured nuts have dug corresponding sized ruts in the sand. The up side is that the bottom of my diffs will always be nice & shiny??

The trick is get 2 sets of tyres. Then you can have your road set and you play set.

Originally Posted by George130

The legal way to solve it is with an engineers certificate. Otherwise you can't put them on.

Not in QLD - practically impossible to get larger tyres engineered.

When/if the NCOP comes in, 50mm larger will be possible.

EDIT - don't go by the sizes on the sidewall. Check the rolling diameters on the tyre manufacturers website. In practice you can usually go 1" lerger in diameter without a problem.