A recent thread on another forum (A2OC) made me think:
Why are we told to test tyre pressures when cold and adjust accordingly, but told to check engine oil level when warm? Is this not the same theory but in reverse?
My point being, this morning it was ~0C. If I adjusted my tyres to 30psi then drove 150 motorway miles, the pressure at the end of the journey would be ~36psi, I imagine.
But what if the ambient temperature was 30C and I adjusted the pressures to 30psi then the tyres would be 36psi by the end of the journey.
Which is the correct pressure that the OEM requires?
Which leads me to: Nitrogen filled tyres will expand less than air filled. So therefore shouldn't Nitrogen tyres be filled to higher than OEM stated pressure when cold?
Why are we told to test tyre pressures when cold and adjust accordingly, but told to check engine oil level when warm? Is this not the same theory but in reverse?
My point being, this morning it was ~0C. If I adjusted my tyres to 30psi then drove 150 motorway miles, the pressure at the end of the journey would be ~36psi, I imagine.
But what if the ambient temperature was 30C and I adjusted the pressures to 30psi then the tyres would be 36psi by the end of the journey.
Which is the correct pressure that the OEM requires?
Which leads me to: Nitrogen filled tyres will expand less than air filled. So therefore shouldn't Nitrogen tyres be filled to higher than OEM stated pressure when cold?
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