Tractor tire liquid ballast
Pick your tire size. See how many gallons go in at 75% fill and how much weight it adds — water or calcium chloride.
What to know before filling
- 75% fill (“valve level”, valve at the top) is industry practice: the fluid covers the valve and the rim, and air on top keeps the tire cushioned.
- Water freezes at 32 °F. Calcium chloride 3½ lb per gallon stays slush-free to −12 °F; 5 lb per gallon to −53 °F. It is heavier, but corrodes steel rims if it leaks — use a tube or a corrosion-resistant rim.
- Tables assume type 1 calcium chloride (77%). With type 2 (94%), use 25% less CaCl₂.
- Narrower or wider rim than in the table: −4% / +4% per inch.
- For beet-based fluids and antifreeze, use the fluid maker's chart — densities differ.
- Liquid adds weight to one axle. Check axle loads with the ballast (axle load) calculator, and remember the Continental data book's rule: as little as possible, as much as necessary.
Source: Firestone Ag, Tire Info — Hydroinflation (firestoneag.com), 75% fill tables; 238 rows checked: water weight = gallons × 8.34 lb and solution totals add up; 5 inconsistent rows left out. Checked October 2026.