In my last column, we reviewed inflation pressures for bias vs. radial tires and implement tires. As you saw, sometimes you need to know more than just simply inflating the tire for its most demanding application.
This column continues our discussion of the slight, simple nuances regarding inflation pressures for certain machines of which every tire dealer should be aware.
Tractor tire inflation pressures are a fairly complex matter. The mechanical configuration, as well as the applications, have a major influence on these pressures. One of the largest problems is the disparity in recommended air pressures for high-speed roading versus the operational pressures that are optimal for field operations.
The vast majority of tractors that work in field operations also have considerable time in high-speed road applications running from field to field. The inflation pressures for optimal performance are quite different, and there is no happy medium. The pressures need to be set for the most demanding application, which is normally during high-speed operations. If the pressures are set for roading, the pressures will be considerably higher than what is needed for optimal performance during field operations.
No farmer is going to take the time and effort to adjust his inflation pressures when changing from field operations to roading and vice versa. Air inflation systems would make this possible, but there are not many options on the market at this time.
The “IF” and “VF” technologies do help with this issue. With this technology, the pressures are set for the maximum weight carrying requirements outside of the speed. This technology enables the tires to carry about 20% more load than standard radials with the “IF” technology and 40% more load with the “VF” technology. This technology may be a good solution to the inflation pressure variability needed for roading versus in-field operations.
Small two-wheel-drive tractors fitted with bias tires are simple. Quite often, these are fitted with front-end loaders and are utilized occasionally by small landowners for many different operations. In these situations, the air pressures should be maximized in the front-wheel positions and likely maximized in the rear.
If a two-wheel-drive tractor is fitted with radials, it should be inflated to the most demanding application. When the tractor is fitted with a front-end loader, your customer needs to inflate the fronts to their maximum. The rears can be inflated to the most demanding application which may be less than the maximum inflation pressures.
Rear tire inflation pressures quite often are determined by what type of implement is attached to the three-point hitch and its weight. Ultimately, the inflation pressure is determined by the load on each axle as well as the maximum speed.
Mechanical Front-Wheel Assist
This segment is very diverse because of the extreme variability in horsepower and applications. The cardinal rule is to inflate to the most demanding application. Keep in mind that the most demanding application may not be when the maximum load is being carried since the maximum loads are quite often carried while running lower speeds during field operations.
Always check the recommended inflation pressures for higher speeds when roading the tractor between fields because the higher the speed, the more demanding the application becomes for your customers’ tires.
The larger MFWD tractors are predominately fitted with radials. If your customers’ tractor is not roaded at higher speeds, they can set the pressures for heavier loads at reduced speeds. This is really ideal for field operations because their tires will have optimal inflation pressures for field work, and they will get the maximum benefits and performance out of their radials.
Check out the rest of the May digital edition of Tire Review here.