A 2024 F-250 Super Duty can hold 50 gallons of diesel (DEF tank capacity is 7.5-8 gallons).

The 2024 F-250's main fuel tank holds 50 gallons of diesel, while its Diesel Exhaust Fluid (DEF) tank typically ranges from 7.5 to 8 gallons, depending on configuration. DEF refills are less frequent than fuel, with an average range of 5,000-10,000 miles per tank.

Key Fuel & DEF Specifications

  • Fuel Tank: 50 gallons (diesel only; gasoline models vary).
  • DEF Tank: 7.5-8 gallons (6.6L Power Stroke engine).
  • DEF Consumption: ~1-3 gallons per 800-1,000 miles.
  • Low DEF Warning: Triggers at ~10% remaining (~0.75-0.8 gallons).

DEF vs. Fuel: Range & Refill Comparison

Metric Diesel Fuel (50 gal) DEF (7.5-8 gal)
Avg. Range 600-800 miles (12-16 mpg) 5,000-10,000 miles
Refill Frequency Every 500-700 miles Every 5-10 oil changes
Cost to Fill $150-$250 (varies by fuel prices) $15-$30 (DEF ~$2.50/gal)

What Happens If DEF Runs Out?

  1. First Warning: Dashboard alert at ~10% DEF remaining.
  2. Reduced Power: Engine derates to 5 mph if ignored after ~500 miles of warnings.
  3. No Restart: Vehicle won't restart until DEF is refilled (emissions compliance lock).

Tips to Maximize DEF Efficiency

  • Avoid short trips-DEF consumption increases with frequent cold starts.
  • Use high-quality DEF (ISO 22241 certified) to prevent sensor clogs.
  • Check DEF levels every 3-5 fuel fill-ups (or via dashboard menu).
  • Store DEF in cool, dry conditions (degrades above 86°F/30°C).

Common DEF Myths Debunked

  • "DEF freezes in cold weather." False-it thaws naturally and won't harm the system.
  • "Aftermarket DEF voids warranty." False if ISO-certified.
  • "DEF reduces engine power." False-it only affects emissions, not performance.