Im pretty comfortble in my assessment. I have compared my odo to the hoghway markers on a handful of times over decent stretches of ~30-50 miles. I get a multiplier for 33s on mine of 1.12 times the odo.

Triple is right about showing less miles, so you need to mark the odo reading up to compensate before you do your MPG calc.

Big Truck: 00, 3.5, Endeavor, 5-Spd drive line in hand!
Little Truck: 87, 2.6T I/C, MT, LSDs, Tonneau Top
Her Truck: 03, 3.8, 20th Anniv, 65k
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