On mine, the odometer reads about 20k, I add 55k to that. I'm not overly concerned about the odometer, If I ever sell it, I have good supporting evidence that the real mileage is the odometer, plus 55k.
ALSO - If you can determine its a bad speedometer, you can find a place to send your cluster and they will fix it.
If you have a smart phone, consider buying a blue tooth ODBC scanner tool. These are great for reading engine codes etc.
https://www.amazon.com/BAFX-Products.../dp/B005NLQAHS
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