MerCruiser Complete Driveshaft / Gear Housing Assembly
Alpha One Gen. II
| MerCruiser OEM | Ratio | Rotation | Note |
| 5121200TP | 1:47:1 | Standard Rotation (RH) | |
| 5111200TP | 1:47:1 | Counter Rotation (LH) | |
| 5121300TP | 1:62:1 | Standard Rotation (RH) | |
| 5111300TP | 1:62:1 | Counter Rotation (LH) | |
| 5121400TP | 1:81:1 | Standard Rotation (RH) | |
| 5111400TP | 1:81:1 | Counter Rotation (LH) | |
| 5121600TP | 2.00:1 | Standard Rotation (RH) | |
| 5111600TP | 2.00:1 | Counter Rotation (LH) | 0W535509 and below |
| 5121700TP | 2.40:1 | Standard Rotation (RH) |
Extra information
| Engine model |
Single engine gear ratio |
Gear ratio high altitude |
Twin engine gear ratio |
| 3.0L | 2.00:1 | 2.40:1 | 2.00:1 |
| 3.0L MPI | 2.00:1 | 2.40:1 | 2.00:1 |
| 4.3L 2-barrel | 1:81:1 | 2.00:1 | 1:81:1 |
| 4.3L 4-barrel | 1:62:1 | 1:81:1 | 1:62:1 |
| 4.3L MPI | 1:62:1 | 1:81:1 | 1:62:1 |
| 4,5L 200 | 1:81:1 | 2.00:1 | 1:81:1 |
| 4,5L 250 | 1:62:1 | 1:81:1 | 1:62:1 |
| 5.0L MPI | 1:62:1 | 1:81:1 | 1:62:1 |
| 350 MAG MPI | 1:47:1 | 1:62:1 | 1:47:1 |
| 357 4-barrel | 1:47:1 | 1:62:1 | 1:47:1 |
5121600TP 1x present small corner from cavitation plate, see photo further new tail.
