I have a 1998 explorer that is moving about 5-6mph faster than the speedometer registers. My son has found this out twice now! What steps do I need to do to fix this. Is it the cable? something worn? what? Are the parts only available at the dealer, or at a local auto parts store?

 

Is the Explorer running stock sized tires? If it is, you may have a bad VSS (Vehicle Speed Sensor) in the tranny. If it a bad VSS, you cangetone from WWW.ROCKAUTO.COM for about $10-20 depending on what tranny you have.

 

Many after market programmers allow you to calibrate your speedometer based on the NON-OEM Tires youmay have put on your vehicle.

They are however very expensive and in your case not worth the cost if correcting your speedometer error is all you are worried about, but they also read and reset trouble codes, and allow you to set other parameters like Max Speed, Rev limiters etc....

Good luck and post back with the final solution so we can all learn from this.

 

The tires were replaced approximately 2 years ago with theoem specified size. This problem is a recent one.Is there a mechanical speedo cable from the trans to the speedometer? Or, is it an electrical connection to the back of the speedometer?