Does anyone know if it hurts the transmission to shift from drive to neutral while driving at speeds over 45mph? I was thinking I could coast to stop signs on my way to work on less busy roads to help save on gas. Sounds pathetic, but hey money is money.
It may not hurt your transmission, but then again, it might if the transmission doesn’t have an rear oil pump. But no matter how your transmission is constructed, what you are contemplating will not save gas.
If you coast while in gear, your engine will actually go down to its normal idle speed, which is exactly what it will also do if you coast in neutral. So–no money saved on gas, but you will be putting more wear and tear on the transmission each time that you put it back into gear.
Ergo–this could actually cost you more in the long run, not to mention the fact that coasting in neutral is illegal in most jurisdictions.
No, it will not hurt the transmission. Transmissions like neutral. But your fuel savings will be nil. You’d do so much better simply leaving a larger gap from the car in front of you.
Taking your foot off the gas earlier would probably help just as much. You are on the right track anyway.