WHY CAN"T I SEE MY MILEAGE ON THE DASH
it could be the following (speedometer heads) or the (speed sensor) you may what to check the gears on the on the speed sensor for damage...
I bet this is a case of someone changed a setting on the display, so instead of displaying mileage your showing some other function like tire pressure of what have you. Open your owner's manual and it'll tell you how to get the dash to display mileage again, in most cases it's a button near the dash that cycles through various features.
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