Commonly overlooked, transmission gearing is a very important factor when building a mud rig. Here is a listing of the popular rear wheel drive GM automatic transmissions. See where your transmission stacks up, most importantly where your first gear stacks up. Check back next week and I’ll have list for the Ford guys.
| Trans Type | First | Second | Third | Fourth | Fifth |
|---|---|---|---|---|---|
| ALLISON 1000 | 3.10 | 1.81 | 1.41 | 1.00 | 0.71 |
| POWERGLIDE | 1.82 | 1.00 | - | - | - |
| POWERGLIDE | 1.76 | 1.00 | - | - | - |
| Turbo 4L60 | 3.06 | 1.62 | 1.00 | 0.70 | - |
| Turbo 4L60E | 3.06 | 1.62 | 1.00 | 0.70 | - |
| Turbo 4L80 | 2.48 | 1.48 | 1.00 | 0.75 | - |
| Turbo 4L80E | 2.48 | 1.48 | 1.00 | 0.75 | - |
| Turbo 350 | 2.52 | 1.52 | 1.00 | - | - |
| Turbo 400 | 2.48 | 1.48 | 1.00 | - | - |
| Turbo 200-R4 | 2.74 | 1.57 | 1.00 | 0.67 | - |
| Turbo 700-R4 | 3.06 | 1.62 | 1.00 | 0.70 | - |