How to Calculate Rear End Gear Ratio

The rear end gear ratio of your particular automobile will indicate the balance in power and speed of your specific car. Most high-performance sports cars have a higher gear ratio of 3.5-4.2 s, which demonstrates their exceptional speed but lack of power in comparison to a truck. Rear-end gear ratios are very easy to calculate, and in some cases you may not even need to jack up the rear of your car to count the gear teeth. If you do need to raise up the rear of the car, be sure to use a car jack on either side of the car for safety reasons.

Things You'll Need

• Car jacks (if necessary)
• Calculator

Instructions

1. Raise the car on the car jacks, if necessary. Make sure to place the car jacks under the appropriate slots on the rear of the car.

2. Count the number of ring gear teeth on the specified gear you are calculating.

3. Count the pinion gear teeth on the same gear.

4. Divide the number of pinion gear teeth by the number of ring gear teeth. The resulting number is the rear end gear ratio.

References

• Chevy Hiperformance: How To Calculate Rear End Gear Ratio