A temporary diesel fuel waiver in Texas is creating an important warning for construction equipment owners. Although the measure is intended to ease fuel supply disruptions, John Deere is reminding operators that not every diesel engine can safely use the higher-sulfur fuel now permitted under the emergency rules.
On October 20, 2026, the U.S. Environmental Protection Agency (EPA) renewed its temporary waiver of ultra-low-sulfur diesel requirements in Texas. The extension allows higher-sulfur diesel to be distributed through November 13, 2026, giving fuel suppliers additional flexibility during ongoing supply disruptions. However, the waiver does not change the fuel requirements of modern Tier 4 engines.
Why Higher-Sulfur Diesel Can Damage Tier 4 Engines
John Deere Power Systems warns that Tier 4 Interim and Tier 4 Final engines must continue using ultra-low-sulfur diesel containing no more than 15 parts per million (ppm) of sulfur.
Higher-sulfur fuel can create problems for the advanced exhaust aftertreatment systems used in these engines. These systems include diesel particulate filters (DPFs) and selective catalytic reduction (SCR) technology, which works with diesel exhaust fluid (DEF) to reduce harmful emissions.
According to Deere, using fuel that exceeds the recommended sulfur limit may not cause immediate engine failure. However, prolonged exposure can contribute to aftertreatment system degradation and shorten the service life of critical components.
There is also a potential financial consequence. Using fuel that does not meet the specifications in the equipment owner’s manual could affect warranty coverage for related engine components.
Which Equipment Can Use the Waiver Fuel?
The temporary waiver is not a blanket approval for all diesel-powered machinery.
Older off-road equipment with engines certified to Tier 1, Tier 2 or Tier 3 standards may be eligible to use higher-sulfur diesel, provided the fuel meets the requirements specified for that particular engine.
Modern Tier 4 Interim and Tier 4 Final engines must continue using diesel with a maximum sulfur content of 15 ppm. Equipment owners should not assume that a machine can use higher-sulfur fuel simply because it operates off-road.
The distinction is especially important for construction companies operating mixed fleets. An older bulldozer, excavator or wheel loader may have different fuel requirements from a newer machine working at the same jobsite.
John Deere’s Recommendations for Equipment Owners
To reduce the risk of fuel-related damage, Deere recommends several practical steps:
- Verify fuel sulfur levels: Contact the fuel supplier directly to confirm that diesel meets the engine’s specified sulfur limit.
- Check the owner’s manual: Review approved fuel types, filtration requirements and maintenance intervals for each machine.
- Use approved fuel filters: Ensure replacement filters meet John Deere performance standards to protect fuel system components.
- Check engine certification: Confirm whether each machine uses a Tier 4 Interim, Tier 4 Final or older emissions-tier engine before selecting fuel.
These precautions are particularly important for contractors, equipment rental companies and fleet managers responsible for multiple machine models.
Protecting Equipment Through Proper Maintenance
Fuel quality is only one part of maintaining construction machinery. Regular inspection of fuel filters, hydraulic systems, cooling components and undercarriage parts can help identify problems before they lead to expensive downtime.
For excavators, loaders and dozers, worn tracks, rollers, idlers and sprockets can also reduce operating efficiency and increase maintenance costs. Using compatible replacement components and following recommended service intervals helps keep equipment productive.
FL Machinery supplies replacement parts for excavators, loaders and dozers, including undercarriage and hydraulic components. Contact our team with your machine model or part number to identify suitable parts and request a quotation.
Dozerpart Operation Team
2026.10.4
