Chrysler Repair: 1989 Dodge Dynasty Odometer, mechanical speedometer, dodge dynasty

Question
The odometer on this car is not working, but the speedometer is working OK.  Is there something I can do or replace to fix the odometer?  Thanks.

Answer
Hi Randy,
I don't know if it is 16 or 20 tooth gearing. The gears I am speaking of are in the speedo/odo head unit of the instrument cluster. So I would remove the cluster and inspect the unit to see which gears it has. But I have learned something new by reading my '89 shop manual more closely.
Interestingly, while many of the '89 model year Chrysler cars had eliminated the mechanical speedometer cable, it appears that the New Yorker/Dynasty still used that cable for the speedo function but had adopted an electronic distance sensor which is positioned on the top side of the transaxle extension housing (the box from which the half shafts are driven) and which sends a pulsed signal (eight pulses per wheel revolution) to the engine controller and the cluster for the transmission and odometer to function properly.
So this bifurcation has made modify my recommendation:
I would verify whether you have a mechanical speedocable and an electronic odocable. If they are indeed separate then I would check the distance sensor by removing its electrical plug and putting an ohmmeter across its terminals. Then lift the right front wheel and observe whether the ohmmeter pulses when you rotate the wheel. If it doesn't pulse then that is why the odometer doesn't function*. It it does pulse the the gears in the odometer head are the reason that it doesn't function. I am glad you asked, otherwise I wouldn't have discovered this 'mixed' situation. The manual may or may not be accurate, but I would definitely check this out before buy the odometer gears. Instead you may need the distance sensor which unfortunately is more expensive but you might find a used one at a junk yard.
Roland
*The distance sensor is gear driven by the right half axle. If the sensor is not removed from the trans when the half axle is removed (for example to change a cv-boot) then the gear of the sensor will be damaged. Thus you might really have a damaged sensor rather than damaged gears in the speedo/odo head unit. Was you right half shaft recently serviced? If so, maybe you can get the shop to pay for a new sensor.






Hi Randy,
There are a couple of gears in the unit that drive the odometer and those wear out. I understand that a company sells these gears for $25. Try
www.odometergears.com
for information about their availability.
Roland