Marking of disks - what it is necessary to know to the private motorist

The first wheel was invented long before the appearance of cars. When and by whom this greatest discovery was made, it is still unknown. It is believed that it was first used in Mesopotamia for more than five millennia ago, and the first wheels with spokes appeared in Asia Minor (on the territory of modern Turkey) after another 1,500 years, and then spread rapidly around the world. Anyway, any, even ultramodern, wheel disks are a further improvement of one of the most ancient inventions of mankind.

The wheel disks are made of steel and light alloys. Steel is stamped from a single sheet, and then the parts are welded together. As a result, they produce rather high-quality and durable products. They are easily restored in case of damage. Their main disadvantages are the following: they have too much weight and are not highly accurate in manufacturing.

Lightweight alloy is not inferior in strength to steel, but at the same time give ample opportunities in the field of wheel design. In addition, they have a higher accuracy of manufacture and excellently divert heat from the brake unit.

Regardless of the material and the method of manufacture, all these products have standard markings. Disc labeling contains all the necessary information about the product. It is on its inner surface, and must also be contained on its packaging (box, sticker, booklet, etc.).

So, what is the labeling of disks? How to understand the symbols? Let's consider how the marking of wheel disks is performed, for a specific example: 8.5Jx16H2 5 * 120 ET 45 d 74.1, where

• 8.5 - the width of the disc (in inches).
• J - the shape of the rim. Contains information about the so-called hampa (protrusions along the lip of the tubeless tire), designed to securely fix the bead of the tire.
• X is the rim type (the detachable is indicated by the symbol "-", the one-piece - "x").
• 16 - wheel rim diameter (in inches).
• H2 - information about the presence of hump.
• 5 * 120 - the number of bolts or nuts, as well as the diameter of the mounting holes.
• ET 45 - take-off (removal) of the disk (in millimeters). The distance is called the distance between the caster (part of the wheel to which it contacts the hub) and the conditional plane dividing the wheel in half. It can be either positive or negative or zero.
• D 74.1 - hub diameter (in millimeters).

In addition, disc labeling provides additional information. The following is indicated:

• The manufacturer of the disc;
• Date of manufacture (as a rule, this year and week: 1209 means that the disk was manufactured in the 12th week of 2009);
• The stigma of the supervisory authority;
• Maximum allowable wheel load (in pounds or kilograms);
• Permissible tire pressure;
• Stigma of x-ray control;
• Stigma of the State Standard (in Russia it is Rostest).

Now you know how to label the disks. All details were given above. Such a seemingly complicated procedure, like decoding the marking of disks, will not become a "Chinese letter" for you. You will be able to choose what is right for your car.