Hilux Tyres

Speak to toyota or your tyre dealer - order a hilux standard placard ie not sr5. They came out with 16" cheese cutters which are slightly taller than the oe 15" ones. Might just make you legal.

You can do all your diameter differences etc via this web site.

www.101tires.com/TireSizeCalculator.asp

I have 17" wheels and tires on my 05 Hilux and they work out to be around 5% bigger in rolling diameter, speedo adjusted to suit etc. This was all done by the dealer.

Any more specific questions should be made to an authorised tire outlet I would think.

I think the key here is to use your exact words "The Apparent Law" . I don't know of an exact law on tires and their diameters, perhaps someone could shed some light. My primary concern was sticking within a 5% increase, I ended with that exactly. I specified 17" wheels as being an optional extra fitted, the insurance co didn't want to know anything else. Sticking within the 5% tolerance on rolling diameter meant that the vehicle would not suffer in any way shape or form, in fact we know better tires and wheels will improve the vehicles handling if done correctly. I understand your concern , if you choose a 16" package that is a little different in rolling diameter , but only 2-3% different I don't think you should worry about it. My other concern was the speedo for obvious reasons, this was adjusted by the dealer before delivery. My tint shade on my windows may be slightly illegal to, but I'm not going to lose any sleep over it. LOL

Follow up

Well I informed them of the exact issue, sizes, apparent laws etc. It got refferred to the underwriters and has come back approved without any change to my bill. Gunna get it in writing from them. At least now it's all squared up and they won't be getting me on that one.

No guarantees if any of you decide to inform your insurers however, as I was nervous for while that they may come back and refuse to insure me altogether and that was certainly on the cards.