It is forbidden to mount truck tires on the same axle, in simple or twin,:
– of different brands,
– of different sizes,
– of categories of use other road tires, special tires or snow tires (with marking M + S). What matters is the category of use and not the sculpture of the tire (sculpture of the tread),
– of different structures (radial or diagonal),
– of different speed categories,
– of different load capacity indices.
For secure mounting
Tires with different tread patterns can be mounted on the same axle if:
– they are of the same brand,
– have the same size,
– have the same structure,
– are of the same category of use,
– have the same speed category,
– they have identical load capacity indices.
We recommend mounting tires with the same tread pattern on the same axle.
WEAR OF THE TIRES
The depth of the main grooves in four points evenly distributed on the tire circumference must not be less than one millimeter more than one point in four.
According to an extract from the Highway Code:
– except for those for public works vehicles, the tires must have an apparent tread pattern all over the tread;
– no canvas must appear on the surface nor on the bottom of the sculpture;
– the tires must not have any deep tear on the sides.
CHECK OF WEAR STATE
Wear verification must always be carried out at different points on the tire.
This check can be performed using a depth gauge or by observing the tread wear indicators, whose presence is indicated on the side by a symbol (little Michelin man).
If the legal or technical wear limit has been reached, the tire must be disassembled and replaced.
In the event of abnormal wear or a difference in wear on the tires of the same axle, contact a professional.
ASSEMBLY OF RECOUNDED TIRES
According to the Highway Code it is possible to mount tires regrinded both on the front axles and on the drive axles of heavy trucks of more than 3.5 t, also for the transport of people or dangerous materials.
ASSEMBLY OF RECONSTRUCTED TIRES
The characteristics of retreaded truck tires that must be common for tires mounted on the same axle are:
– the brand of the reconstruction company,
– the size of the tires
– the structure of the tires,
– the speed category and the load indexes of the tires
– the same category of tire use.
IT IS FORBIDDEN to mount on the same axle different retreaded tires of any brand whatever the mark of the carcass.
It IS AUTHORIZED mounting of retreaded tires of the same brand whatever the mark of the carcass.
Mixed assembly, on the same axle, is possible only if:
– the brand of the reconstruction and that of the new tires is the same;
– the brand of carcasses are the same (new and rebuilt).
The technical characteristics of retreaded and new tires on the same axle, which must be identical, are:
– the brand of the carcass and the retreaded tire,
– the size of the tires,
– the structure (radial or diagonal),
– the speed category and load indexes,
– conditions of use (road, off-road, snow – marking M + S).
REPAIR OF TIRES
During its life, a Truck and bus tyres are subjected to many stresses and can be damaged in different ways.
It is dangerous to neglect a damage. Under certain conditions, MICHELIN truck tires can be repaired; this possibility was foreseen by the planning.
All damage cannot be repaired.
Repairing a tire is the prerogative of trained and qualified professionals. The repairer is always solely responsible for the relevance and quality of the intervention on the tire.
The repair is always preceded by the disassembly and careful checking of the tire (internal and external) by a professional.
DURATION OF THE TIRES
Tires are made of different materials and components whose properties change over time. This evolution depends on the storage conditions (temperature, humidity, position, etc.) and use (load, speed, inflation pressure, condition of the wheels, etc.) to which the tire is subjected.
Since the aging factors are variable and difficult to measure, beyond the regular controls implemented by the user, Michelin recommends periodic inspections made by a qualified professional who will determine the tire’s ability to continue the service.