Martyn (WA) replied:

Seany,
By the time I write this there will be other replies, from what I've learned the legal lift you can do is 50mm and this is measured by the eyebrow height at the wheel arch, this is the figure the boys in blue are interested in, obviously you can either do a body lift (bushes between the body and the chassis) or a suspension lift, bigger springs and shocks shackles etc etc. If you do either and you increase the eyebrow height more than the standard measurment by 50 mm you should have an engineers cert to say it's ok, this could involve a lane changing test to prove the stability of the vehicle, from what I hear this can costa lota money $2000 +. The placard you talk about is the GVm of the vehicle which can't be exceeded even if you fit heavy duty everything, again i imagine if you got an enginers cert maybe, but the load rating of your tyres and a whole bunch of other stuff comes into this equation.
I could well of missed the mark in some points but when I looked at doing mods (putting another engine in) the paperwork I had to do to make the vehicle legal and still insurable made going beyond the design envelope prohibitive, i gave up in the end, the insurance was the killer, in the big scheme of things not worth the effort and in my case the money.
Others may be able to help you with other aspects. Keep the shiny side up

Truckster (Vic) replied:

A lift is anything above standard height.

Doesnt matter what you use, tires, shocks, body mounts etc, anything bigger than OEM is a lift.

ross replied:

I found when I was on the pricing trail for my springs that all the aftermarket ones had a 2in lift whether you wanted it or not .I shudder to think of buying new springs from Toyota.

craig replied:

this also begs the question about a 4x4 that comes standard with hight ajustable suspension , ie the range rover ? can you legaly lift it 50mm if so what hight do you take if from as it has 4 hight settings ?