1. What is Final Drive?

Final drive is the overall gear reduction between the engine and the wheels, calculated by multiplying the transmission ratio by the axle ratio. It determines the vehicle's torque multiplication and top speed capabilities.

2. How Does the Calculator Work?

The calculator uses the final drive formula:

Where:

• Transmission Ratio — Gear ratio of the selected transmission gear
• Axle Ratio — Gear ratio of the differential/axle assembly

Explanation: The final drive ratio represents the total reduction from engine RPM to wheel RPM, affecting acceleration, towing capacity, and fuel economy.

3. Importance of Final Drive Calculation

Details: Calculating final drive ratio is essential for vehicle performance tuning, determining proper gear selection for specific applications, and understanding the vehicle's power delivery characteristics.

4. Using the Calculator

Tips: Enter transmission ratio and axle ratio as decimal values. Both values must be greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical final drive ratio?
A: Final drive ratios typically range from 2.5:1 to 4.5:1 for passenger vehicles, with higher values providing more acceleration and lower values offering higher top speeds.

Q2: How does final drive affect performance?
A: Higher final drive ratios improve acceleration and towing capacity but reduce top speed and fuel efficiency. Lower ratios have the opposite effect.

Q3: Can I change my vehicle's final drive ratio?
A: Yes, by changing the differential gears, but this modification affects overall vehicle performance and should be done with consideration of intended use.

Q4: How does final drive relate to RPM at speed?
A: Higher final drive ratios result in higher engine RPM at any given speed, while lower ratios allow the engine to operate at lower RPMs.

Q5: Is final drive the same for all gears?
A: No, the transmission ratio component changes with each gear, so final drive is different for each gear selection.