AG TIRE TALK KEY TAKEAWAYS
PRECISION INFLATION: Like to Cut Your Fuel Bill by 5 to 10%? Changing Tire Pressures is the Answer!
YOKOHAMA: —tires have a significant impact on fuel efficiency. That means good decisions on tires can have great impacts on fuel costs.
PRESSUREPRO: Michigan State University Extension estimates that poor tractor performance wastes 150 million gallons of fuel each year in the United States alone.
TRELLEBORG: Testing has shown that Hybrid Tread Design more closed tread pattern can reduce fuel consumption by up to 8%.
DORAN: Roughly 30-40% of the fuel required to move a vehicle down the road is spent overcoming tires rolling resistance.
MICHELIN: In fact, independent studies at Harper Adams University in the UK show fuel consumption can be reduced by 10% by changing to VF Tires…
BKT: There are several factors to consider when working to enhance fuel economy… Proper Ballast, CTIS, VF Technology, and choosing lower rolling resistance tread designs when applicable play a MAJOR ROLE decreasing fuel consumption and reducing fuel costs.
MAXAM: Correct ballast, with wheel or suitcase weights, designed to adjust the axle loads, can reduce tire slippage, reduce soil compaction, and reduce rolling resistance which will lower fuel consumption.
FIRESTONE: As the tread depth decreases below 20% of its original depth, consider replacing the tires—this is when they may start losing traction, especially in wet soil conditions.
We have a packed blog post with fuel reduction tactics ranging by category, providing up to 10% FUELS SAVINGS!
- If you like, view Manufacturer’s Answers by Savings CATEGORY:
VF TECHNOLOGY Fuel Savings: https://agtiretalk.com/vf-technology-fuel-savings/
PROPER BALLAST Fuel Savings: https://agtiretalk.com/proper-ballast-fuel-savings/
HYBRID TREAD DESIGN Fuel Savings: https://agtiretalk.com/hybrid-tread-design-fuel-savings/
CENTRAL TIRE INFLATION SYSTEM Fuel Savings: https://agtiretalk.com/central-tire-inflation-system-fuel-savings/
BKT USA, Inc.
Dave Paulk: Manager Field Technical Services
There are several factors to consider when working to enhance fuel economy in the field. When these things aren’t working right, it can increase the cost of fuel and time, as well as wear and tear on the tractor.
The correct amount of wheel/tire ballast is important for a tractor because it helps to transfer the power from the tractor to the ground. With too little ballast, you are limited to the size of the implements/wagons you can pull. This can create too much tire slippage (tires spinning faster than the groundspeed of the tractor) and can cost you in fuel and time. 8% to 15% slippage is in the recommended range per industry standards.
Field vs Road Air Pressure
Tractors are used in the field and on the highway. Proper air inflation and proper ballast are important to ensure that a tractor performs at an optimum level. Different air pressures are needed for both applications for proper performance of the tractor.
- FIELD: Tractors in the field used at lower speeds can run less air pressure to allow for a longer and wider footprint. This helps with traction, minimizes soil compaction, and saves fuel. Over inflation in the field can cause excessive wheel slip and fuel use.
- ROAD: When the tractor is on the road and used at higher speeds, tires need more air pressure to carry the weight of the tractor and implements. Load capacity decreases as speed increases, therefore, more air is needed to protect the integrity of the tire. More air creates a smaller footprint for the road that gives less rolling resistance and better fuel economy.
CTIS Accommodates Field & Road
Central air inflation systems on tractors and combines are starting to be more widely considered and used. A compressor mounted on the tractor and air lines connected to the tires allow for air pressures to be dropped in the field and air to be added to the tires before road use. This can ensure that tires are used with the proper air pressure for the application. Incorrect air pressures for diverse applications can cause a variety of problems with the tires, including premature wear, tire casing failures, and impact breaks. Correct air pressures can save time, fuel, and money.
Up to 20% Fuel Savings
There have been many studies done on fuel usage on farms. Since fuel is one of the largest expenses on the farm, it is wise to consider ways to save money on fuel. One survey has stated that by using the correct air pressures (minimum pressures that will carry the weight of the tractor and implement) can save up to 20% in fuel savings. Another study suggests that by eliminating excess slippage by using the correct amount of ballast can lead to up to 10% in fuel savings. There are so many things that can affect the amount of fuel used, it is hard to pinpoint one thing. It is commonly agreed that running the correct air pressures for the load and speed, correct amount of ballast and weight distribution, reducing rolling resistance and reducing slippage can surely help with fuel savings.
VF Technology Fuel Savings
VF rated tires carry 40% more weight than a standard tire at the same air pressure. They can also carry the same load as a standard tire at 40% lower air pressure. The VF tire is a good option to consider if no till/minimum till is used on the farm. Air pressure dictates the ground bearing pressure of a tire. The lower air pressure needed, the less ground bearing pressure on the soil. The more air, the greater the ground bearing pressure that is applied. VF tires provide a larger footprint to reduce slippage, minimize soil compaction and save fuel. At times, the weight carrying capacity and speed rating of a VF tire is needed. For heavy tractors, sprayers, and other equipment, the VF tire is the best choice to consider. Also, if less air pressure is desired for field work, the VF rated tire is the better choice.
Lower Rolling Resistance Hybrid
Several hybrid tread designs have been introduced into the market in the past few years. They work best for tractors that are on the road most of the time. When the correct air pressures are used, this tire design will wear smoother and provide good road traction in the summer and winter. They will deliver better fuel economy on the highway as they are made to have less rolling resistance. The hybrid designs are gentler on the ground as they have more of an R-3 design than an R-1 or R-1W bar design. BKT makes the IT696 and the IT697 in this design, Both with 40 mph speed ratings. For smaller tractors, the BKT RT333 is a hybrid designed for vineyard and orchard applications working well on the road with good traction in the dirt. It is gentler on the soil than a chevron type tread.
Proper ballast, changing from Road to Field Air Pressure with CTIS, using VF Technology, and choosing lower rolling resistance tread designs when applicable play a MAJOR ROLE decreasing fuel consumption and reducing fuel costs.
Maxam Tire International
Greg W. Gilland: Business Development & Ag Segment Manager
Ag tires are the integral component that connects the farm machinery or vehicle to the ground whether working in the field or on the road. Over the last eighteen months, we have seen both fuel and fertilizer prices increase dramatically driving up the operational expenses of farmers and growers. Finding creative ways to manage the escalating fuel and other operational costs can reduce the impact of these expenses in any farming operation.
With the objective of finding ways to mitigate operational expenses to maximize profit and increase crop yields, MAXAM has put together the below table as a summary of suggested best practices or tactics that can help reduce the farmer or grower’s fuel expense:
|Best Practice||Suggested Activity||Expected Benefit or Result|
|Manage Tractor or Vehicle Weight||Modern tractors are outfitted with wheel or suitcase weights designed to adjust the axle loads to achieve the best possible setup based on the towed implement’s weight. If possible, avoid using water or liquid ballast in tires as it creates additional weight and greater rolling resistance.||By ensuring the proper weight set up of suitcase or wheel weights for each type of tractor (2WD – MFWD – 4WD) operators can reduce tire slippage, reduce soil compaction, and reduce rolling resistance which will lower fuel consumption and improve overall machine efficiency delivering fuel savings.|
Manage Tire Slippage or Slip Rate
|Most tractors have an onboard slip meter to measure the amount of tire slippage that impacts the utilization of the tractor and the resultant fuel consumption by managing the optimal slip rate.||Optimized tractor slip rates will reduce fuel consumption per below guidelines:
· 2WD Tractors = from 10% up to 15% Slip Rate
· MFWD Tractors = from 8% up to 12% Slip Rate
· 4WD Tractors = from 8% up to 10% Slip Rate
|Manage Tire Inflation & Maintenance||The pressurized air in the tire cavity carries 80% of the axle or vehicle weight, therefore, air pressure management has a direct impact on how the machine operates. Adjusting the working air pressure by axle load will ensure the best possible tire footprint. New Machinery with onboard air pressure monitoring and inflation adjustment systems allows for constant air pressure optimization based on axle load & speed.||Underinflation or Overinflation can increase fuel consumption by creating greater rolling resistance, whereas constantly managed air pressures either manually or through onboard inflation systems could reduce fuel consumption by 15% in 1 year – all by reducing slip which increases traction (tire footprint), resulting in improved productivity and fuel savings.|
Changing or Manage Tire Technology
|Moving from Bias to Radial tires will improve your machine’s fuel productivity due to the increased tire footprint or contact patch, providing greater traction.||Radial tires, due to their casing construction which acts like an independent suspension system, will optimize the size of the tire footprint ensuring the best possible traction, reduced slip, and greater contact patch which can produce a minimum of 15% fuel savings in a one-year period.|
|Choose VF & D Speed Rated Tires||VF Tire Technology allows for 40% more load or 40% less air pressure for a given axle load. Using this technology effectively can allow you to improve your fuel efficiency due to the improved tire footprint, delivering greater traction.||As machines continue to get heavier as axle loads and horsepower continues to evolve, VF Technology can offer the best possible tire footprint if optimized to the right air pressure based on its axle load. At the right air pressure, the D Rated rubber compounds designed for high speed and high loads will offer reduced rolling resistance without compromising traction or footprint ensuring improved fuel efficiency.|
MAXAM’s continuing objective for 2022, and for the years to come is to deliver superior radial products in the right sizes, with the right load capabilities, that when operated at the right air pressure will deliver the value and fuel savings our customers expect from our tires.
Jason Zaroor: President/CEO
A four-letter word lately in more ways than one, remains one of the largest expenses for growers. With prices soaring, and pricing out of farmer’s control, it’s more critical than ever for operations to combat fuel waste and boost efficiency. Fortunately, one of the easiest ways to make significant impacts in adding fuel efficiency is maintaining optimal tire pressures– with and proven Tire Performance Management technology makes doing so easier than ever.
Bottom Line Savings
We’re not just talking fuel savings, but also reduced soil compaction, improved yields, and reduced operating costs. BIG $.
Cost of Soil Compaction
In fact, a 2020 study conducted by the University of Minnesota and North Dakota State University found that soil compaction could cost farmers in North Dakota and Minnesota alone, over $587 million over two years, for every 10% of land affected by compaction. Further research shows soil compaction can slash yields by up to 15% in a single year and continue to negatively impact yields for up to 10 years. These numbers are staggering, and don’t even take into account bloated maintenance cost for your equipment experienced from harder pulling, decreased tire life experienced from running improper pressures or the cost of your increase field time experienced from added slippage.
150M Gallon US Opportunity
A bulletin from Michigan State University Extension estimates that poor tractor performance wastes 150 million gallons of fuel each year in the United States alone.
Opposite the On Highway Tire world, for farmers to hit ideal field performance, ag tires need to be maintained at optimal ‘low/correct’ pressures, to allow a larger footprint of the tire to hit the ground resulting in improved pulling ability, reduced tire hop and more- all resulting in increased fuel efficiency.
CTIS & TPMS:
While both CTIS (Central Tire Inflation Systems) & TPMS (Tire Pressure Monitoring Systems) are both tools that maintain optimal pressures, as their names suggest, how they do so varies.
CTIS are plumbed units that leverage an on-board compressor to help automatically regulate tire inflation, while TPMS utilizes tire mounted Sensors to deliver real time tire performance readings to operators. Both provide significant benefits to farmers by providing the data and or tools to easily monitor and regulate inflation. Due to a few key benefits, including ease of installation and lower cost ($1,000 vs $average CTIS – $25,000), here, we’re going to focus in on how TPMS can add efficiency and savings to your operations.
How TPMS works:
Direct TPMS technology leverages two main components – tire mounted Sensors and an in-cab display or integrated box. Sensors sample real time tire pressure data and report it utilizing RFID or Bluetooth technology to an in-cab mounted display or reading device, arming operators with real time readings and alerts. In advanced TPMS options, such as PressurePro’s offerings, tire performance data – including both pressure and temperature readings – can also leverage enhanced monitoring capabilities to provide numerous additional options including integration to existing vehicle networks or screens, remote monitoring and more.
Great news is that installation is a snap. All you do is replace valve stem caps with our sensor, then hook up the software.
Savings & Safety
Domestically engineered and produced PressurePro TPMS remains a pioneer of TPMS technology, original equipment on Case IH, providing proven durability, adding safety and savings for drivers and operators of all types.
Further, improved equipment management enabled with our advanced monitoring provides opportunity to increase yields, reduce field time, decrease maintenance, extend tire life, and improve fuel efficiency and more.
David Graden: Operational Market Manager – Agriculture
There are many things that can be done to reduce fuel consumption and add money to your bottom line.
To start with, make sure you fit your equipment with the right tires for the application. What I mean is, if you are using a scraper pan, make sure your tires are designed for this application. The most costly thing you can do, in this application, is to destroy a set of tires that were not designed to be used in high torque scraper applications, then find out the manufacturer doesn’t cover their product due to the misapplication.
Run Recommended Air Pressure
Next, be sure your tires are set to the manufacturer’s recommended air pressure, based upon speed and weight of your machine. If air pressures are set higher than the recommendation, you risk lug damage, punctures, fuel consuming slip and soil compaction, which negatively affects your yield in the long run. By using recommended air pressures, your fuel consumption is reduced due to the larger footprint on the ground. Keep in mind, this is contrary to what we know about passenger car tires. In the soil, a larger footprint means more tractive capacity/less slip.
Make it a VF tire and you have significantly improved upon this idea, as they are designed to carry same weight at 40% less air pressure. Less slip translates to improved productivity and, therefore, less fuel is consumed to do the job.
In fact, independent studies at Harper Adams University in the UK show fuel consumption can be reduced by 10% simply by changing to VF Tires, as shown in below example:
Let’s take a look at proper ballasting next. For a front wheel assist, we tend to lean towards a 40% front and 60% rear weight split. For 4×4, it’s around a 55 front/45 rear split. Proper ballasting not only improves your efficiency, but it also reduces stress on your machine’s transmission. Improper ballasting can create power hop in the field and road loping while driving down the road. Both can be dangerous and difficult to control. In the field, power hop is commonly caused by one axle rolling faster than the other and, in essence, the machine is fighting itself. When your machine is properly ballasted between front and rear, the tires, at proper air pressures, will be in sync.
For example: a MFWA machine fit with 480/80R50 rears and 420/85R34 fronts, improperly ballasted, may require 12 psi on the rear to carry the rear weight, and 28 psi on the front, to carry the front weight. As a general rule of thumb, this gap of more than 10 psi will create some major issues. These tires are matched up to fit within the tolerance of the machine’s transmission. With 28 psi on the front and only 12 psi on the rear, the rolling circumference of each tire is being pushed outside of the transmission’s tolerance and creating power hop. You may think, “I’ll just increase the air pressure of the rear to keep the tires within 10 psi.” Well, that will may likely solve your power hop issue, but you just increased your slip by reducing the size of your footprint on the rear. On the flip side, if your tractive capacity on the front is far greater than the tractive capacity on the rear, you didn’t fix anything, and power hop still exists. In either situation, a lack of efficiency consumes more fuel and costs you more.
Central Tire Inflation System
Finally, you could even take one more step toward total efficiency and invest in a Central Tire Inflation System (CTIS) by Michelin owned PTG. This proven technology allows an operator to run most Michelin tires down as low as 6 psi (depending on the weight of the machine) in the field, which maximizes footprint and traction, then up to the tire’s maximum air pressure for road speeds, which reduces rolling resistance and improves stability at higher speeds. In either case, applying this technology could earn you up to 10% fuel savings! Now, couple that with the proven 4% gain in yield from reduced soil compaction and you’re adding tens of thousands back to your bottom line! To add the cherry on top, these systems can be transferred from one machine to another, as your trade cycle dictates.
At Michelin, we train and equip every one of our sales reps with the tools and skills to properly ballast and recommend air pressures specific to your application and needs. Don’t hesitate to reach out to your local Michelin sales representative now, for further information, and at no additional costs: https://agtiretalk.com/technicalcontacts/
Yokohama Off-Highway Tires America, Inc.
Blaine Cox: National Product Manager—Agriculture, Golf and Turf
Because they are the point of contact between the machine and the ground—and the point of friction when unnecessary motion takes place—tires have a significant impact on fuel efficiency. That means good decisions on tires can have great impacts on fuel costs.
The most important decision is inflation pressure. Here’s why: when manufacturers design a tire, we determine how much its sidewalls will flex in order to create a contact patch with an optimal size and shape. Too much inflation pressure means less contact patch, more slip, and less engine power turned into forward speed. That all adds up to more fuel consumption.
In practical terms, we can be talking about a lot of fuel. In fact, scientists at the University of California, Davis found that correctly inflating tractor radials (in their example, 13 psi front/11 psi rear rather than overinflated at 24 psi) reduced fuel consumption by 20%.
If you are experiencing too much slip because your equipment is too light, ballast your tractor to optimize it. If the slip is the result of worn-out tread failing to provide enough traction, consider replacing your tires. Whatever the reason for it, slip is just another word for turning your wheels and burning fuel without getting work out of the process.
Selecting the right tire can pay off in lower fuel bills. Because IF and VF tires have added flex in their sidewalls, longer and wider contact patches, and can operate at lower inflation pressure, they improve fuel economy over standard radials.
When you are looking to upgrade your tires, look for tread patterns that maximize traction and minimize rolling resistance. We’ve come a long way from the lug designs that were in fashion for more than 100 years. You’ve got great choices for the soil types, roading needs, and chores you need to accomplish, from two-level lugs on the Alliance Agri Star II to the hundreds of biting edges on the innovative block tread pattern of the Alliance 363 and 550 radials.
Finally, when diesel prices are as high as they have been this season, a central tire inflation system (CTIS)—which allows you to adjust inflation pressure on the go, right from the cab—can pay itself off more quickly than ever. And not only does CTIS improve fuel economy, it also helps you get longer wear and better performance out of your tires.
So when you start thinking about fuel consumption, take a minute to glance away from your gas cap and take a look at your tires.
Precision Inflation Systems
Ken Brodbeck: VP of Technology
Like to Cut Your Fuel Bill by 5 to 10%? Changing Tire Pressures is the Answer!
On our 1200 grain farm, the fuel bill was a painful necessity. My guess is the same is true on your operation.
- Setting tire pressure on your Ag. machines is just as important as setting your combine correctly for either corn or soybeans.
- If the combine is not set just right, grain/money goes out the back end. The same is true for your tires. Fuel is wasted with too much pressure in the field, along with yield loss from soil compaction. And tires wear out and/or fail early if they are set too low.
What to Do?
- Check the tractor companies’ suggested ballast recommendations for your machine’s task. Planting will be lighter than heavy tillage in the fall. Ballast and adjust tire pressures accordingly.
- Weigh each axle so you can set the tire pressure per the tire manufacturer’s minimum pressure for the heaviest condition. Typically, this is the road transport.
- Your soil, tillage practices and hills may call for more ballast. How do you tell what is the right ballast?
- Wheel slip for radials should be in the 8 to 12% range for the best fuel efficiency. Sounds high right? Wrong! A lot of tractors are running consistently at 2 to 3% slip. The trouble is at 2% to 3% slip you are are burning extra fuel just to drag the tractor up and down hills while creating more soil compaction. Not Good.
- Lighten the tractor, especially for planting and possibly even grain cart work. If the slip goes up to 15% climbing one steep hill in the field, no problem and your fuel bill will thank you.
- Why raise tire pressure for the road? Per a University of California Davis fuel economy test with standard tires, not IF or VF, they showed fuel economy improvements on the road of 7.3% for + 7 psi and 11.4% for + 14 psi above the standard minimum pressure!!
- Europe has been using Central Tire Inflation (CTI) for over 30 years. This gives you the best of both worlds. High pressure for better fuel economy over the road and lowest pressure for the maximum traction and fuel efficiency along with minimizing soil compaction and increasing yield 2 to 4%.
- 200 bushel corn x 6 $/bushel x 2% = an extra $24 per acre!
- 24 x1000 acres = $ 24,000 per year. You may be losing $ 24K with high tire pressures in yield alone!
- Bottom line: Investing in a tire inflation system on tractor and planter can pay for itself in 1 to 2 years on yield alone, not including fuel and tread wear savings.
Contact us at Precision Inflation, we can help: https://agtiretalk.com/technicalcontacts/
Ross Ormsby: Director of Project Management
Roughly 30-40% of the fuel required to move a vehicle down the road is spent overcoming tires rolling resistance. When tires are underinflated, the amount of drag created by the tires increases which will reduce your fuel economy. Doran tire monitoring systems provide real-time inflation pressure data for all tire positions to help ensure vehicles aren’t operating on underinflated tires.
Trelleborg Wheel Systems
Chris Neidert: Marketing, Training and Development Manager – AG
Proper Ballast Set Up
Getting as much horsepower as possible transferred from the engine to the ground is the end target. Ballasting can help accomplish this by either adjusting existing weights or placing additional ballast (weight) either on the front or rear of the tractor. The goal isn’t to have 0% wheel slip – but to shoot for a preferred slip of between 8% and 15% for tractors.
- Having too high a slippage rate means spending more time than necessary in the field and wasting money on fuel as the tires are forced to spin more.
- Having too little slip means risk of overload on the tires, higher soil compaction, power loss, increased fuel consumption and lower productivity. Getting the proper ballast and tire inflation pressures can optimize traction, reduce compaction, increase the life of the tires, and increase productivity.
Capitalize on Engine Power
Regardless of the tractor horsepower that you are using goal is to capitalize on the engine power. Getting the tractor to be heavy enough to apply that power from the engine to the ground is paramount. This illustration shows that engine power turns into torque and assisted by the tires creating friction to the ground provide grip. The ultimate result is traction. This traction is what we are looking for to reduce spin and maximize fuel and reduce time.
WHEN do you need Ballasting?
- The weight/power ratio of the tractor is not enough, in particular when high traction is required.
- Tractor is unbalanced due to the use of additional equipment, and it is necessary to redistribute the axle weight. We must add weight to the opposite axle according to the implement to achieve proper axle weight ratios.
- For field preparation in low torque condition and on prepared field, to avoid an excessive soil compaction.
- High percentage of road travel
What TYPE of Ballasting is best?
It consists of the partially filling of the tires with water and/or antifreeze solutions. This is an economical method to add weight. Its use is only recommended in high torque applications, in particular on dry and tough soil, where you need to increase the weight/power ratio of the tractor. It is not advisable to use water ballasting for road transport. It is more difficult to handle the tractor, it increases the fuel consumption, increases braking time and causes rapid wear of the tires. Trelleborg does not recommend using liquid ballast. It stiffens the tire and reduces the footprint increasing compaction, reduces the ability of the tire to flex, can cause corrosion of the rim and creates additional inertia on the wheel when moving.
CAST IRON WHEEL FLANGE Ballast
Normally used to increase the weight/power ratio and improve traction. It is recommended for use in high torque applications on the field. Also, for road transport on HP tractors in order to avoid excessive wheel slipping at the start
Advantage: No Weight on the Axle. Disadvantage: Difficult to apply, Increased Cost
CASE WEIGHT Ballast
One option is cast iron plates or cast iron in one block fitted on the front part of the tractor: normally used to load the front axle and balance the weight distribution. It is recommended for tractors working in the field with a carried implement. Also, for road transport.
Advantages: Easy to Mount / Dismount.
Trelleborg recommends Case Weight ballasting!
Now, let’s determine what the tractor SHOULD weigh for its application. Below are guidelines:
- Use a calculation of 100 – 120 pounds per horsepower of the tractor. Example – a 200 horsepower tractor should weigh between 20,000 lbs. – 24,000 lbs.
MFWD (Mechanical Front Wheel Drive)
Distribution should be between 40-45% on the front axle and 55-60% on the rear axle. If the design of the implement creates a high load on the rear axle (reducing the load in the front axle), the ratio on front wheel assist tractor should be closer to 45-50% in the front and 50-55% in the rear
Distribution should be 50% on the front axle and 50% on the rear axle for 4WD
The front axle should have between 25-35% of the total load.
It is very important to measure this weight per axle with calibrated scales (individual per tire or per axle, like on a grain elevator scale or actual axle weighing scales). Your Trelleborg or Mitas sales representative can help.
- An incorrect weight distribution can create issues like “power hop” where the front axle is too “light” (losing traction) and the rear axle is overloaded creating excessive “grip.”
- When a customer has power hop issues, it’s a clear indication that the total tractor weight and/or weight distribution is not correct for the application. This issue can be fixed by correcting the ballasting without the need to change tire size or tire ratio. Air pressure can also be a factor.
Now that we have talked about tractor ballasting and weight distribution, optimum tire performance continues with proper air pressure. What carries the load in a tire?? ITS AIR!!
- The actual pressure of the tire must be established in accordance with the mechanical characteristics of the vehicle, the additional load from the use of equipment as well as the load conditions. This pressure must be checked at ambient temperature. These recommended pressures can be obtained from the load/pressure/application tables according to the use. Checking the pressure with a reliable air gauge and then consulting the tire manufacturers Load Tables will give you the recommended air pressure for the application. Consult with Trelleborg/Mitas personnel with help in calculating your correct air pressure.
- Many times, users will judge the air pressure in a tire by its looks. You cannot accurately determine a tire’s air pressure by looking at the tire. Many users will see the sidewall squatting out and think the tire pressure is too low. With today’s radial tires, the sidewall bulge is perfectly normal. You need an accurate air gauge and the target air pressure to be sure. Many times, new tractors will be delivered with the tires overinflated. This could be due to the tractor manufacturer has overinflated the tires for more tractor stability on the trailer during shipment.
In our example below, you can see the footprint differences between the two pictures. These are thermal images taken with the same tire (480/80R50) at two different air pressures.
LEFT Footprint is overinflated for the application, contact area is small, and there is too much heat generation in the lugs.
RIGHT Footprint has correct air pressure obtained from its load table.
Better Traction = Less Fuel
You can see footprint is wider and longer, placing more lugs on the ground. Traction will be increased, resulting in less tire spin; thus, less fuel consumption.
VF technology has two main advantages – using less air pressure (up to 40%), or being able to carry more load (up to 40%).
Less Air Pressure
In North America most producers tend to go with the less air pressure feature, as it creates a bigger footprint, providing:
- More Traction – more tire on the ground translates to more lugs on the ground which gives more traction. Less slip in the field, less time to complete your work and less tire spinning means less fuel consumption.
- Less Compaction – crop roots can spread out and create a higher yield.
CTIS (Highly Recommended)
As tire professionals, in most ag tire applications, we recommend the ideal environment for an ag tire is one air pressure (lower) in the field and another air pressure (higher) on the road. Central Tire Inflation Systems (CTIS) can provide this option. Running multiple air pressures can provide many benefits – bigger footprint in the field for less compaction – more tread on the ground for more traction – more tread on the ground for better wear and a smoother ride. On the road, a more stable tire for handling and better road wear.
Hybrid Tread Design
Matching the correct tread pattern to the application will dramatically help with tire wear, fuel consumption and ride. Below you can see an example of two distinctly different tread patterns.
Figure LEFT is a perfect tire to use when you are operating more on hard surfaces and do not need a lot of traction. The design will provide some traction, but ride comfort and tire wear will be the advantage. Testing has shown that the more closed tread pattern (left) can reduce fuel consumption by up to 8%.
Figure RIGHT works exceptionally well in operating conditions that require an aggressive tread for more traction.
In sum, you have 4 primary ways to reduce fuel costs: Improve Ballast, Precisely Manage Inflation with CTIS, use VF Technology, or reduce rolling resistance with a Hybrid Tread Design. When everything is dialed in just right, the fuel savings are big!
Austin Fischer: Firestone Ag Field Engineer
Tactics to Reduce Fuel Costs
To truly optimize fuel usage, growers must set the correct inflation pressure for each application. Other tactics to reduce fuel costs include replacing worn tires, removing unnecessary ballast, replacing liquid ballast and implementing a central tire inflation system (CTIS).
- Set the correct inflation pressure: Most growers use their tractor for more than one application throughout the year. Examples include planting in the spring and knifing anhydrous once crops are growing—or spraying in the summer and pulling a grain cart in the fall. To reduce fuel costs, it’s important for growers to determine the appropriate inflation pressure for each application and to be sure to maintain it. Firestone Ag’s tire inflation pressure calculator can help with this. The equipment operator’s manual can be very helpful as well.
If a grower doesn’t plan to adjust tire inflation pressure throughout the year, we recommend setting the pressure for the maximum load the tires will see all year. Still, the best way to maximize fuel efficiency is to adjust the inflation pressure for each specific application throughout the year.
- Check tread depth and replace worn tires: The tread of a tire is what transmits the power from the tractor to the ground. As the tread depth decreases below 20% of its original depth, consider replacing the tires—this is when they may start losing traction, especially in wet soil conditions. Growers should also replace tires when signs of damage or degradation become apparent.
- Replace liquid ballast: Adding liquid ballast to tires increases the maximum amount of draft a tractor can exert, but it can reduce fuel efficiency in some situations when compared to using wheel weights. This is due to the stiffening effect of the liquid on the tire’s carcass, which causes it to deflect less and results in a smaller footprint. The smaller footprint translates to less lug surface area available to develop tractive force. Moving away from liquid ballast, and calcium chloride, for example, also removes the chance for corrosion of the tire rims, which would eventually necessitate tire replacement.
- Implement a Central Tire Inflation System (CTIS): A CTIS system allows the operator to run the optimal pressure, both in the field and on the road, to unlock maximum wear performance, improve traction and reduce fuel use due to less tire slip.
Let’s consider a grower who uses a 36-row semi-mounted planter. When it’s raised up and in its transport configuration, this adds a significant amount of weight to the tractor’s rear axle. However, when it’s in the field planting, most of that weight will no longer be on the tractor, but on the soil. With a CTIS system, the grower can reduce the inflation pressure of the tires on the rear axle on-the-fly to maintain the optimal footprint. A tractor without CTIS will need to maintain the pressure required for transporting the planter even though it may be significantly more than what is needed at the time.
Products to Further Reduce Fuel Consumption
The bigger the tractor or implement, the more important it is to make sure it’s riding on the right tire. The wrong tires can decrease fuel economy and potentially lower yields due to increased compaction.
Two options available to farmers to enhance fuel cost reduction include upgrading to increased flexion (IF) and very high flexion (VF) tires. When switching from standard to IF/VF, growers can increase efficiency up to 4%. Those using bias tires can experience an increase in efficiency up to 14% when upgrading to radial tires, which also provide better tire longevity and fuel economy as well as reduced soil compaction.
- Upgrade to IF/VF tires: IF and VF tires offer elongated footprints by either permitting the same load at a lower inflation pressure or a higher load at the same inflation pressure. In turn, this extended footprint increases the contact area between the tread lugs and the soil, improving the ability to transmit the torque of the machine to the soil without slip. This equals better fuel economy and less time in the field due to decreased slippage and increased traction. Per unit of fuel, growers should be able to travel further and get out of the field sooner than they would otherwise.
- IF tires can carry up to 20% more load than a standard radial at a given inflation pressure—or they can carry the same load (as a standard radial) at a lower inflation pressure.
- VF tires can carry up to 40% more load than a standard radial at a given inflation pressure—or the same load (as a standard radial) at a lower inflation pressure.
Firestone’s IF and VF tires engineered with Advanced Deflection Design (AD2) technology represent the “next generation” in performance and productivity for today’s farming needs. Firestone’s AD2 technology delivers more load and more traction, saving time while burning less fuel. Other benefits include reduced soil compaction and improved ride.
- Switch from bias to radial tires: The unique construction of a radial-ply tire allows the carcass to be more flexible and able to develop a bigger and squarer footprint than a similarly sized bias-ply tire. The increased footprint size leads to reduced contact pressures exerted on the soil, increased flotation and more lug surface area available to develop tractive force without slipping—increasing fuel economy. The squarer footprint shape leads to improved wear performance, ride comfort and handling when roading.
While some specific agricultural needs and equipment may call for the bias-ply option, Firestone Ag recommends radial tires in nearly all cases, given their long life, smoother ride and better performance characteristics.
Contact Firestone’s Field Engineering team for further questions and assistance: https://agtiretalk.com/technicalcontacts/
All information is provided in this blog solely to provoke thought. All deductions made from information on this site must be confirmed by Certified Ag Tire Dealer before use. Ag Tire Talk does not recommend anyone conduct tire service work with exception of Certified Ag Tire Dealer Professionals.