Best way would be to check your odometer ison a measured highway for at least 100 miles. You can use any interstate or freeway that has mile markers. This would show any inaccuracy in your odometer.

I checked my 300SD this way for 400 miles and found the odometer to me accurate within 0.15 percent (15/100 of 1 percent) which is about as close as you can get after a tire size change from 195-80R14 to 205-70 R14.

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