First I have every hear of that. I'd have to do some research to confirm. Got a link to confirm? All the docs I have read have never seen speed ratings mentioned.
All I know is that all tyres sold and fitted in Australia to light motor vehicles have to be rated at 180kph or higher.
But for load ratings, you must be equal to or higher, never under the load rating specified.
---------- Post added at 04:54 PM ---------- Previous post was at 04:49 PM ----------
Found it:-
It is strongly recommended that the speed rating of the tyres fitted should be equal to or better than the rating ofthe original tyres fitted by the vehicle manufacturer, however:
•
If the speed rating of the tyres specified for your vehicle is higher than 140km/h, you may fit tyres with alower speed rating but not lower than 140km/h.
•
If the replacement tyres fitted, including winter tread tyres (commonly called “mud and snow” tyres) and
retreaded tyres
, have a speed rating less than that shown on the vehicle’s tyre placard, a warning label must
be affixed to the vehicle (usually by the tyre dealer) which states:
Sux to be in NSW... Maybe!!!
The tyre placard on a modern Mazda doesn't specify that a certain tyre speed rating, just shows the tyres fitted to the MPS.
I have seen other older placards that state a certain load rating and speed rating are required.
If your placard doesn't have those specifications down the bottom, then you can ignore that rule in NSW.