Garmin RV760RV speed vs F-53 speedometer
I'm pulling out all the stuff we took out of the coach for the winter. While I was updating my Garmin 760RV I recalled some behavior that I find a bit strange. The Garmin tells you your speed and it agrees with the coach speedometer up until you reach about 55 MPG. Then the two diverge, with the Garmin reading 2-3 MPH more than the coach speedometer. At 65 MPH on the Garmin, the coach is reading about 67 MPH. Once you get to about 70 MPH, the two start agreeing with one another again.
I'm thinking that for some reason the coach speedometer isn't linear in the 55-70 MPH range, but can't think of a reason why it would be. I'm running under the assumption that the GPS is more accurate as it its measuring actual rate of change in your coordinates and doesn't care about things like tire OD, but that's just an assumption.
Does anyone else with a Garmin see this type of behavior?
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