[Nissandriver]

I never would have guessed this. I would have guessed a colder tire would be firmer (less pliant) reducing rolling resistance. Racing cars need their tires warmer to increase grip. In racing a warmer tire is ¨stickier". You´d think a sticky tire would have more rolling resistance? This test might be a good example of my perception differing significantly from reality.

Was the tire pressure equalized at the different temperatures? If the pressure was set at one temperature and only the temperature was changed for these tests, what would the tire pressure change be at the various temperatures? I know the pressure would reduce as the temperature falls. Did tire pressure play any part in these differences in the test?

Here´s a little tidbit I checked recently. I drove from NM (6500 ft elevation) to Pensacola, FL (60 ft elevation). I checked the cold tire pressure at both locations at similar temperatures and found 40 psi when I began the trip in NM and 39 psi in Florida the morning after I arrived. I have seen larger changes in tire pressure in my truck driving between similar elevation changes.