Tyre Learn

Regardless of the brand of tyres on your vehicle, you must be aware of their characteristics, maintenance instructions and other variables that are essential to getting the best performance and containing your costs.


Use adequate tools and lubricants to mount and dismount tyres.  Do not use substances derived from petroleum. They can damage the tyre.

  • The inflation of the tyre has to be done inside a safety cage to avoid any accident.
  • Always check the inside of the tyre to verify that there is no residue or objects after the assembly between the tyre and the rim so there is no damage to the tube.


  • Use the correct size of the tube for each tyre.
  • Tubes and belts are not reusable.  They have to be replaced at the end of the tyre life.  Do not use expanded tubes or that have being repaired several times.


Tyres should not be used when the tread wear indicator is exposed in any tyre tread.  The tread wear indicator bars are moulded into the tread and are located at the bottom of the tread grooves in several locations around the tyre. When the tyre is worn-out where any of them become visibly flushed with the adjacent tread ribs, it is time to replace the tyre (Tread depth limit 1.6 mm.).


Due to the irregularities of the road, tread wear will not be uniform and tyre rotation is recommended to help improve tyre performance.


Well-maintained alignment, suspension and steering components helps to improve toughness of your tyres and promote uniform tread wear.


Balancing helps to provide correct distribution of the tyre mass along the circumference of the tyre and rim assembly. With the proper balancing of your tyres, you avoid vibration, shimmy and irregular tread wear.


The correct air pressure to inflate your tyres is determined by their load index.  Weigh your vehicles as a normal practice to verify the load that each position of the vehicle has and the total load of the vehicle. Use the table of air pressures to determine the correct inflation of your tyres.


The air pressure of your tyres has to be monitored periodically and has to be done with professional air pressure gauges. Remember to always check air pressure when tyres are cold.

Load Index

Load Index determines the maximum weight a tyre can carry.  It is an industry standard that determines the maximum service load on a tyre at the correct air pressure. 

For more information, view the table showing the correct load index of each tyre for single and tandem axles.

Air Pressure

The correct air pressure must be in accordance with the position of the tyre on the vehicle and the total load (single axle or tandem axle). This helps to promote better performance of the tyre, more kilometres run, keeps the carcass in good condition for future retreads and helps uniform tread wear. The table indicates the correct air pressure of each tyre according to its load index.

View Chart

Read the line of the tyre size (295/80R22.5) where the load index is (152/148), check the load by tyre in the tandem axle line the corresponding load (2740) and in the single axle line, check which is the load for each tyre (2730).  When you locate the load in kg in the corresponding line, you must use the air pressure determined at the top of the column and use it to inflate your tyre.

Tandem axle assembly for a load of 2740 Kg by tyre, recommended pressure 105 lb.
Single axle assembly for a load of 2730 K. by tyre; recommended air pressure 90 lb.

Speed Symbol

Determines the maximum speed a tyre can run with a maximum load that corresponds to its load index, as specified by the tyre maker.  See the table with technical information of each tyre in the Tyre Applications Guide to know the tyre speed symbol.

EXAMPLE: TYRE 295/80R22.5 G358 152/148 L
L: is the speed symbol that according to the table corresponds to the maximum speed of 120 km/h that the tyre can run if it is inflated with the correct air pressure determined by the load of the tyre.

(Km / h)
(Km / h)

Load Variation

It is possible to transport more weight that the one determined in the load index only if the operation maximum speed decreases according to what is established in the speed symbol table.

This table shows this relationship.

*(1) Speed (km/h): It is considered, for the above table, as the maximum speed the vehicle can reach completely loaded.
*(2) Speed symbol (km/h): indicated the speed that a tyre can stand with a determined load, according to the tyre application.
*(3) Load - kg/tyre used in a normal ride.

EXAMPLE: TYRE 295/80R22.5 G358 152/148L
As determined in the service description, each tyre can transport up to 3550 kg (load index 152) when it is mounted in a single axle and up to 3150 kg (load index 148) when is loaded in a tandem axle, observing the maximum speed of 120 km/h (speed symbol L), air pressure of 125 lbs (as established in the air pressure table).
The load variation table is used in relation with the speed, reading the column corresponding to the speed symbol (L=120), it can be verified that if the maximum operation speed is reduced to 60 km/h (speed line=60), the maximum load can be incremented a 10% in each tyre.
Thus with the same pressure of 125 lbs, the maximum speed of 60 km/h, each tyre will support a maximum load of:

  • 3905 Kg.  In a single axle (3550 Kg increased in a 10%).

  • 3465 kg. In a tandem axle (3150 kg. increased in 10%).


a) Bias and Radial Tyres and millimetre with “F” load capacity use column L=120.
b) Bias and Radial Tyres with a load capacity “G” and higher (Radial tubeless, bias, and Radial with long base use column J=100.