Mechanics

SPEEDOMETER

2001 Ford Explorer • V6 AWD Automatic • 91,500 miles

I done a test to see if my speedometer was accurate, which in this case it is not. It is reading 4-5 MPH too fast. II was going 40 mph (GPS) and it was reading near 46 mph. Is there a fix?
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Cws176
April 4, 2014.




We used to have to replace the gear on the speedometer drive unit with one with the number of teeth specified for the tire size and axle ratio. Since about the late '80s or early '90s those numbers are selected from a list on a scanner and entered into the Body Computer or Engine Computer. The programming has to be changed when different size tires are installed.

Caradiodoc
Apr 4, 2014.
Yeah, it could be the penion gear or tire size? This cheap to fix?
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Tiny
Cws176
Apr 4, 2014.
Pinion gears are cheap, especially if you can find the right used one in a salvage yard. Reprogramming is real fast, but Ford dealers usually charge plenty for the service. Many independent shops have aftermarkert scanners that may be able to do it too.

Caradiodoc
Apr 5, 2014.

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