Tire & Wheel Uniformity and Match Mounting's Role
Match mounting is an often-referred to installation process where a new tire's position on the wheel is selected to help minimize the tire and wheel combination's force variation and/or imbalance. Many installers have asked about the meaning and usage of match mounting and the use of the colored dots on replacement tires.
All Original Equipment tire and wheel suppliers are required to mark the tire's high point and the wheel's low point to help the vehicle manufacturer match mount them. Match mounting helps vehicle manufacturers reduce their cost of balancing weights and minimize new car ride complaints because they start with new marked tires and wheels direct from their manufacturers. Unfortunately many use a temporary tag that is removed before the vehicle is put into service. This means that there often is no permanent mark to reference later.
Although the colors are not standardized, the markings do have the same meaning. One type of match mounting is when the marked high point of a new tire's radial force variation is aligned to the marked (or measured) low point of radial runout of the wheel. The other is when the marked light point of the tire is aligned with the heavy point of the wheel.
There was a time when the valve stem hole on standard wheels indicated the optimum place to which the tire should be match mounted. However, with the advent of styled steel and aluminum alloy O.E. wheels, the stem position evolved into an aesthetic issue rather than being a marker for uniformity. Add to this the likelihood of the wheel retaining its original runout after thousands of miles of travel and you can see that the idea of putting the colored dot at the valve stem is no longer required practice.
We have found that the only way to accurately match mount replacement tires on used original or new aftermarket wheels is to use Hunter tire balancers which have the ability to measure force variations under load before the tire and wheel are installed on the vehicle. Using these machines, the colored dot on the tire might be positioned anywhere on the wheel relative to its runout measurement. In the end, the markers have little, if any, relevance.
Below is a matrix of match mount marking codes for some of the more popular tires and Original Equipment wheels to complement your understanding of the procedure and enhance your ability to successfully address and rectify customer concerns regarding tire match mounting issues (especially when the dots do not align).
| Tire Brand Manufacturer |
|
Tire Static Balance Light Point Indicator | |||||
| BFGoodrich | Yellow Dot | ||||||
| Bridgestone | 1/4" Yellow Circle |
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| Dunlop | Red Dot | ||||||
| Firestone | 1/2" White Circle |
Temporary Yellow Tag | |||||
| General Tire | Paint Dot | Temporary Fluorescent Green Tag |
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| Goodyear | Temporary Fluorescent Green Tag |
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| Kumho | Red Dot | Yellow Mark | |||||
| Sumitomo | Red Mark | Yellow Mark | |||||
| Uniroyal | Mark Just Above Bead | ||||||
| Yokohama | Red Mark | Yellow Mark | |||||
| Vehicle Manufacturer | Wheel Low Point Marks | ||||||
| General Motors | Standard Steel Wheels-Valve Hole (does not apply to styled steel wheels) | ||||||
| Ford | Temporary Chartreuse Sticker (will be removed during new vehicle preparation) | ||||||
| Chrysler | Paint in wheel well (drop center), only visible with tire removed from wheel. | ||||||
| Porsche | Paint in wheel well (drop center), only visible with tire removed from wheel. | ||||||
| Others | Vary | ||||||