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Speedometer Question
- Thread starter hama61
- Start date
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Hi Harry,
The difference will be with the rear axle ratios. The non-overdrive axles had a stock ratio of 3.54:1 while the overdrive version had a stock ratio of 3.909:1. You will need to match the speedometer to the rear axle ratio and not the overdrive type of transmission.
Mark
The difference will be with the rear axle ratios. The non-overdrive axles had a stock ratio of 3.54:1 while the overdrive version had a stock ratio of 3.909:1. You will need to match the speedometer to the rear axle ratio and not the overdrive type of transmission.
Mark
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The face of the speedometer should be marked with a number (small print) which shows the cable turns per mile that it was originally calibrated for. See attached pic which shows 1120. This varies with the axle ratio but not with the transmission.
The axle ratio can be found on a flat horizontal top surface on the differential stamped into the metal as "10/41" for a 4.11 axle. Ring gear has 41 teeth, pinion gear has 10 teeth. See attached pic which shows 10/41.
Approximately, speedometer marked:
1325 = 4.11 axle ratio
1260 = 3.909
1180 = 3.6
1143 = 3.54
D
The axle ratio can be found on a flat horizontal top surface on the differential stamped into the metal as "10/41" for a 4.11 axle. Ring gear has 41 teeth, pinion gear has 10 teeth. See attached pic which shows 10/41.
Approximately, speedometer marked:
1325 = 4.11 axle ratio
1260 = 3.909
1180 = 3.6
1143 = 3.54
D
