Automatic Transmission Fluid (ATF) Drain & Fill Dilution Ratio Calculator
Calculate the exact percentage of clean fresh fluid in your automatic transmission after 1, 2, 3, or 4 drain-and-fill cycles, accounting for fluid trapped inside the torque converter and valve body.
Fresh Fluid Proportion in Transmission (%)
Calculator Inputs
Fresh Fluid Proportion in Transmission (%)
Old Trapped Fluid Remaining (%)
Total Fresh ATF Fluid Used
Transmission Fluid Purity Breakdown: Fresh vs Residual Old Fluid (%)
Volumetric dilution mathematics standard for automotive step-gear automatic (ATF), dual-clutch (DCT), and continuously variable (CVT) transmissions.
This calculator is designed for educational and informational purposes based on publicly declared statutory frameworks. The outputs do not constitute binding financial, tax, or legal advice. We assume no liability for decisions made based on these estimates. Always verify with the relevant official authorities or a certified professional advisor.
Calculation Methodology
Drain Ratio d = Pan Drain Volume / Total Sump Capacity. Fresh Fluid Percentage after N cycles = (1 - (1 - d)^N) * 100. Total Fluid Used = Pan Drain Volume * N.
Frequently Asked Questions
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