Would someone happen to know the GM part# for the correct speedometer gear for a Grand National with 3:73 rear end? I've just resently changed from a 3:42 peg leg to a 3:73 posi unit and my Speedo and Odometer are out. I understand these gears are color coded but a part number would be nice to have when ordering the correct part. Thanks.
The Hurst Olds used 3:73 gears with the 200R4 trans. GM parts books have charts for speedo gears by axle ratio and tire size. Use a Olds chart from a GM parts book
Phil
The 83-84 Hurst Olds, 85-87 442, and 85-88 SS Monte Carlo used a 10 tooth drive, and a 30 tooth driven. All you need to change is the drive gear.