Gear ratios for common GM, Dodge/Ram and Ford automatic transmissions, from first gear to top gear. A ratio above 1.00 multiplies engine torque for acceleration; 1.00 is direct drive; a ratio below 1.00 is overdrive, which lowers engine speed at cruise.
GM transmission gear ratios
| Transmission | Forward gears | Gear ratios (1st to top) | Typical use |
|---|---|---|---|
| 4L60E | 4 | 3.06 / 1.63 / 1.00 / 0.70 | light-duty GM trucks, SUVs and cars |
| 4L65E | 4 | 3.06 / 1.63 / 1.00 / 0.70 | higher-output GM V8 trucks and SUVs |
| 4L70E | 4 | 3.06 / 1.63 / 1.00 / 0.70 | GM trucks, SUVs and cars |
| 4L80E | 4 | 2.48 / 1.48 / 1.00 / 0.75 | GM heavy-duty trucks and vans |
| 6L80E | 6 | 4.03 / 2.36 / 1.53 / 1.15 / 0.85 / 0.67 | GM light-duty trucks, SUVs and performance cars |
| 6L90E | 6 | 4.03 / 2.36 / 1.53 / 1.15 / 0.85 / 0.67 | GM heavy-duty trucks and vans |
Dodge / Ram transmission gear ratios
| Transmission | Forward gears | Gear ratios (1st to top) | Typical use |
|---|---|---|---|
| 47RE | 4 | 2.45 / 1.45 / 1.00 / 0.69 | Dodge Ram 2500 and 3500 trucks |
| 48RE | 4 | 2.45 / 1.45 / 1.00 / 0.69 | Dodge Ram 2500 and 3500 trucks |
| 66RFE | 6 | 3.23 / 1.84 / 1.41 / 1.00 / 0.82 / 0.63 | Ram 2500 and 3500 trucks |
| 68RFE | 6 | 3.23 / 1.84 / 1.41 / 1.00 / 0.82 / 0.63 | Ram 2500, 3500 and 4500 trucks |
Ford transmission gear ratios
| Transmission | Forward gears | Gear ratios (1st to top) | Typical use |
|---|---|---|---|
| 4R70W | 4 | 2.84 / 1.55 / 1.00 / 0.70 | Ford F-150, Mustang and full-size Ford cars |
| 4R75W | 4 | 2.84 / 1.55 / 1.00 / 0.70 | Ford F-150, Mustang and full-size Ford cars |
| 4R100 | 4 | 2.71 / 1.54 / 1.00 / 0.71 | Ford Super Duty trucks and vans |
| E4OD | 4 | 2.71 / 1.54 / 1.00 / 0.71 | Ford F-250/F-350 trucks and vans |
How gear ratios affect your truck
- First gear: a numerically higher first gear (such as the 4L60E’s 3.06) gives stronger launches; a lower one (such as the 4L80E’s 2.48) is gentler but suits heavy, high-torque applications.
- Overdrive: the top gear and your axle ratio together set engine speed on the highway.
- Swaps: changing to a transmission with different ratios changes acceleration and cruise rpm, and electronically controlled units need the right calibration.
Gear ratio FAQ
What are the 4L60E gear ratios?
3.06 / 1.63 / 1.00 / 0.70.
What are the 4L80E gear ratios?
2.48 / 1.48 / 1.00 / 0.75.
What are the 6L80E gear ratios?
4.03 / 2.36 / 1.53 / 1.15 / 0.85 / 0.67.
What are the 68RFE gear ratios?
3.23 / 1.84 / 1.41 / 1.00 / 0.82 / 0.63.
Ratios are the commonly published figures for each transmission design; confirm the details for your exact unit with its documentation. See also: 4L60E vs 4L65E vs 4L80E · 4L80E vs TH400 · 68RFE vs Aisin · transmissions by code · gear ratio calculator.
More guides: 6R80 vs 10R80 ratios · 6L80 vs 6L90 ratios.
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