Ok.
I too want to put 265/45/17's on my WH.
I went to my local tyre guy and he said no more than 15mm.
To which I replied...cr@p!
So I rang the A.C.T. govt motor vehicles tech dept and asked him and he said "15mm max."
I said cr@p!
I said "On my car I want to go up 25mm and its only a 3.5% change and even the speedo will be more accurate."
Then he said "wait a minute, .......your car is a 4x4?"
Off he went then came back after a bit and said, according to "National Code of Practice for Light Vehicle Construction and Modification (NCOP)".....
"The overall diameter of any tyre fitted to an off-road passenger vehicle or a commercial vehicle must not be more than 50mm larger or 26mm smaller than that of any tyre designated by the manufacturer for that model."
I said "what does that mean for me?" So he said "its the Australian National standard and is with 265/45/17's my car would be legally compliant in the ACT."
So I asked my insurance company, they says if it is roadwothry according to the ACT govt then its fine with them.
I draw your attention to the following website.
http://www.infrastructure.gov.au/roa.../vsb_ncop.aspx
Then specifically to the link regarding tyres and suspension page 16 of 71.
NCOP11 Section LS Suspension and steering 3 Feb 2006
I printed it out and took it back to my tyre bloke and he was happy.
