How can I find the correct tyre size that fits my truck or trailer?
Finding out which tyre sizes fits your truck or trailer can be a difficult task. On this page we will explain where you can find the tyre size on you tyre and how you can understand this number.
We will also elaborate on the topics of most common truck and trailer tyre size, the load index of a truck or trailer tyre and the speed index of truck and trailer tyres.
Where do i find the tyre size on my truck?
The tyre size of a truck tyre is printed on the side of the tyre. We call this the 'sidewall' of the tyre. This is a string of information that consists of a combination of letters and numbers. The image on the right shows te tyre size of a light commercial vehicle. You can find the truck tyre size on the exact place.
Hot to read a Truck tyre size?
A truck tyre consists of different elements; the trucktyre width, height, and inch size.
We have found the following number letter combination on the sidewall of a random truck tyre in our warehouse.
Sidewall information: 315/70R22.5
Through this combination we will explain the reading of a truck tyre
The trucktyre width
The width of the tyre is indicated by the first three digits in the tyre size. For example, 315/70R22.5 156/150L is the tread width, 70 is the percentage of tyre height and 22.5 stands for the wheel's inch. Tyre height is indicated after the / in the tyre size.
The trucktyre height
Tyre height is indicated after the slash ( / ) in the tyre size. The height of the tyre is given in percent, a height of 65 means 65% of the width of the tread.
The trucktyre size / Radial tyres
The tyre size of a truck and trailer or semi-trailer is indicated in millimetres. This applies to all radial tyres, a characteristic of a radial tyre is that the tyre size is marked with an R, for example 385/65R22.5.
The trucktyre inch size
Trucks, trailers and semi-trailers can have the following inch sizes 22.5 inch, 20 inch, 19.5 inch and 17.5 inch. The inch size is always indicated at the end of the tyre size. For example, tyre size 245/70R17.5, 245 is the tread width, 70 is the height percentage and 17.5 is the wheel's inch size.
Load index and speed index
After the rim size there are is always a number and a letter. in this case it is 156/150L. The number 156/150 The number indicated the load index of a truck/trailer. We have described the overview that corresponds to the load index number a few paragraphs down.
The last letter in this case L stands for the speed index of the truck/trailer. You can also find this a number of paragraphs down.
Overview of the most common truck and trailer tyre sizes
In the overview on the right you can see the most common truck and trailer tyre sizes.
The first 3 digits are the width of the truck tyre. The 2 digits after the slash ( / ) indicates the height of a tyre in a percentage.
The letter R indicated that the tyre is a Radial type tyre.
The diggets after the R represent the size of the tyre in Inches.
|Truck tyre sizes||Trailer tyre sizes||Flatbed tyre sizes|
Load index of a truck or trailer tyre
The load index stands for the maximum load capacity of a tyre at the ideal pressure, whereby it is important that you never overload the tyres.
During the periodic inspection (APK or TÜV), this is checked and enforced. If you do not have the correct load index on your vehicle, the inspection authority will reject your vehicle. The load index is indicated by codes on the tyre.
The code for the load index is always found on the sidewall of the tyre.
On the right side is a diagram of the index and associated load capacity.
Speed index of truck and trailer tyres
The speedindex of a tyre refers to the maximum speed the tyre can handle. The speedindex is indicated by a letter after the loadindex. For example for a 315/70R22.5 truck tyre the load and speed index is 156/150L, 156/150 is the load index and the letter L stands for the speed index of up to 120 kilometres per hour.
|Speed symbol||Maximum speed (km/h)||Speed symbol||Maximum speed (km/h)|