The manufacturer, manufacturing date/expriation date and tyre size can all be found on your tyres side wall.
Here is how to read your tyre size:
[Width]/[Aspect Ratio] [Type of construction] [Rim Diameter] [Load Rating] [Speed Rating]
i.e. 235/35R19 91Y is 235mm wide; 19% of 235mm high; Radial; 19"; 615kg per tyre; 300km/hr
[Width] The first number is the width of the tyre and it is represented in millimetres or the amount of rubber that meets the road.
[Aspect ratio] This is a ratio for the height of the tyre above the wheel or rim; represented as a percentage of the width of the tyre.
[Type of construction] R = Radial. It is rare to find a car tyre which does not have the letter R. It stands for the construction, which is a radial.
[Rim Diameter] Can range from 10" and 22" for passenger cars. The tyre must have the same inner diameter to fit over the rim correctly.
[Load Rating] This is the load rating which tells the weight capacity for the tyre.
[Speed Rating] The higher the letter, the higher speeds the tyre can handle.
What is a Load Index or Load Rating?
The load rating, represented by the numerical value, is directly related to the maximum weight that each tyre can carry. In this case, 98 would refer to a load capacity of 750kg.
Most passenger vehicle load indexes range from 62 to 126.
Those who off-road or use their vehicle to transport goods will want to use a tyre with a higher load rating compared to those who use their car just for commuting. It is important to note that if you increase the Load Index on the tyres to those above the placard, you should ask what inflation pressure is required to carry the same load as the original tyres. The Tyre & Rim Association of Australia – Standards Manual can assist with ensuring that your new tyres will last the distance by indicating the correct inflation pressures for higher load index tyres.
n all instances, the tyres load index must meet or exceed the value displayed on the vehicles placard, which can be found either in the owner’s manual, drivers-side door, petrol tank flap or in the glove box.
As shown in the below Load Index Table, the greater the load index number, the more weight each tyre can carry.
Load Index Chart
Speed Symbol Chart