Quote:
Originally Posted by GRU
The stock odometer may not be accurate...do a gps distance run and see what your odometer shows compaired to gps distance....gps speed to speedometer is not the same as distance
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Absolutely correct.
My car had 50 series tyres when bought ( 55 series is standard).
When checked against my GPS over my 52 kilometer commute, the odometer was correct and the speedo fast.
After changing to 60 series tyres, my odometer is 5.7% slow and the speedo about 1% slow.
When calculating my fuel consumption I now multiply the odometer reading by 1.057.
As it happens, I've gained about 5% FE, probably due as much to the Kumho KU25 to Pirelli P6 change as to the size change.