Listed gear-ratio data for 2004 Mariner 75 HP outboards. Match your exact model and lower unit; some models may have more than one gearcase configuration.
2004 Mariner 75 HP
Listed ratio values: 2.31:1, 2.33:1
| Model | Gear ratio |
|---|---|
| 75 OptiMax | 2.33:1 |
| 75 TwoStroke - 3 cylinder | 2.31:1 |
| F75 FourStroke | 2.33:1 |
Use the ratio that matches your exact outboard model and lower unit, then enter it in the PropSlip calculator.