Listed gear-ratio data for 2006 Mariner 25 HP outboards. Match your exact model and lower unit; some models may have more than one gearcase configuration.
2006 Mariner 25 HP
Listed ratio values: 1.92:1, 2.25:1
| Model | Gear ratio |
|---|---|
| 25 TwoStroke | 2.25:1 |
| F25 EFI FourStroke - 526 cc generation | 1.92:1 |
Use the ratio that matches your exact outboard model and lower unit, then enter it in the PropSlip calculator.