< Return to News

The Weekly Fill-Up | October 6-10

Harvest Season Market Update: Fuel, DEF, and Propane Trends for Sioux Valley Coop Patrons

As the harvest season intensifies across eastern South Dakota, energy markets are responding to shifting demand across the agricultural sector. For Sioux Valley Coop patrons, this week’s trends bring a mix of stability and subtle movement across diesel, lubricants, DEF, and propane. With combines rolling, grain hauling underway, and heating season right around the corner, staying informed can make a measurable difference in operational efficiency and cost management.

Diesel & Fuel: Steady at the Surface, but Pressure Below

Diesel prices across South Dakota are holding relatively stable, hovering between $3.05 and $3.40 per gallon depending on location and terminal zone. While that offers some short-term relief compared to the volatility of past seasons, national market signals point toward potential tightening as fall progresses.

Inventory levels across the U.S. remain historically lean, and global supply chains are seeing uneven recovery from refinery outages and shipping delays. Even though current prices are steady, the underlying fundamentals suggest that upward pressure could build if regional demand surges or crude prices rebound. For farmers and commercial operators, that means it’s a good time to plan ahead — scheduling deliveries and securing volume before harvest peaks will help buffer against potential late-season premiums.

Oils and Lubricants: Quiet but Critical

While they don’t make daily market headlines, oils and lubricants remain one of the most important—and often underestimated—components of harvest season success. Heavy engine loads and long operational hours are pushing lubrication systems to their limits. The good news is that lubricant pricing remains steady, supported by softening base oil costs tied to recent dips in crude.

However, lead times for specialized oils and additives continue to be stretched, especially in rural distribution channels. Keeping a cushion of essential lubricants, hydraulic fluids, and greases on hand is an easy way to prevent downtime when every minute in the field matters. It’s a smart move for SVC patrons to forecast their oil and filter needs now and align with upcoming service intervals before the heart of winter.

DEF: Still Tight, No Room for Error

DEF supply conditions remain tight across the Midwest. Urea input costs and transportation constraints continue to keep inventories lean, and with increased trucking and harvest equipment use, regional demand is peaking at the same time. No major price corrections are expected this week, meaning the DEF market will stay firm for the foreseeable future.

Running low on DEF during heavy harvest activity can mean costly downtime. Patrons should consider ordering ahead of schedule, maintaining proper storage conditions, and monitoring consumption closely. Treating DEF as a core energy input—not a secondary afterthought—will save headaches and lost hours in the field.

Propane: Slight Uptick Before the Cold

Propane markets are showing a slight upward shift heading into October. Wholesale prices in South Dakota climbed modestly over the past week, and national propane inventories have started to tighten as exports increase and domestic heating demand approaches.

While propane remains relatively affordable compared to other energy inputs, the risk of price escalation increases as winter nears. For those using propane for grain drying, crop drying, or heating, the window for securing cost-effective rates is narrowing. Locking in part of your seasonal supply now provides a safeguard against volatility later in the season, particularly if weather patterns shift colder than expected.

The Bottom Line

This week’s markets paint a picture of relative calm before what could be a more active late-fall energy cycle. Diesel and oil markets are stable, but the underlying conditions are fragile; DEF remains tight; and propane is beginning its gradual climb as demand increases.

Sioux Valley Coop continues to monitor these markets daily to ensure our patrons are supplied, supported, and informed. Whether you’re fueling harvest, maintaining machinery, or heating operations, your local cooperative remains committed to delivering dependable service—and insights that help your business run smoother.

Sources

  1. U.S. Energy Information Administration — Weekly Petroleum Status Report (eia.gov)
  2. WorkTruckOnline — September Diesel Trends Update
  3. Global Petrol Prices — South Dakota Diesel Pricing Data
  4. South Dakota Department of Transportation — Fuel Price Index Reports
  5. YCharts — South Dakota Wholesale Propane Price Index
  6. Argus Media — Northwest Europe Propane Buying Reports, September 2025
  7. BPNews — Propane Use and Agricultural Trends