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🐛 Crawl Ratio Calculator
Calculate crawl ratio, gear reduction, and low-speed control for off-road vehicles
📐 Crawl Ratio Formulas
Crawl Ratio = (1st Gear × Transfer Case × Axle Ratio)
Speed = (RPM × Tire Circumference) / (Crawl Ratio × 336)
Torque Multiplication = Crawl Ratio × Engine Torque
Control Speed = (Engine RPM × 60) / (Crawl Ratio × Tire Revs/Mile)
Crawl Ratio = overall gear reduction, 1st Gear = transmission first gear ratio, Transfer Case = transfer case low range ratio, Axle Ratio = differential gear ratio
💡 Tips
- Higher crawl ratios provide better low-speed control
- Typical crawl ratios: 20:1 (mild), 40:1 (moderate), 80:1+ (severe)
- Consider engine idle speed for control
- Lower crawl speeds allow precise maneuvering
- Torque multiplication increases with crawl ratio
- Balance crawl ratio with highway driving needs