| 1970 Grand Prix Speedometer Gear Usage Chart (Turbo 400) | |||||||
| Speedo Driven Gear | Tire Size | ||||||
| Rear axle ratio | Part No. | Teeth | Color | G78 x 14 | Sleeve & seal assy. | Trans code | Drive gear teeth |
| 2.78 | 1359272 | 38 | BLUE | X | 1362294 | PT | 18 |
| 2.93 | 1359270 | 36 | WHITE | X | 1362294 | PW | 16 |
| 3.07 | 1359271 | 37 | RED | X | 1362294 | PR | 16 |
| 3.23 | 9780470 | 44 | DK GREY | X | 1362293 | PT | 18 |
| 3.23 | 1359273 | 39 | BROWN | X | 1362294 | PW | 16 |
| 3.55 | 1362196 | 43 | PURPLE | X | 1362293 | PW | 16 |
| Information supplied by George Pearson, taken from a Pontiac Parts Book | |||||||