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Mproving fuel economy

I have 2008 Chev Express 6 litre (350 cc). Am working to improve the fuel economy. Does it hurt the transmission to coast in neutral down long hills? The rpm’s go down to 700 from about 1700 when in neutral. Is this much of a fuel saver?

Using neutral probably hurts your fuel economy, most all modern cars shut off gas when you’re coasting and the engines above idle.

It doesn’t hurt the trans it’s just pointless and dangerous.

You can improve fuel economy by keeping the thing maintained well and by unloading un-necessary stuff from the cargo area.

Plan ahead while you are in traffic. Don’t accelerate or brake quickly. If you approach a light slowly and can roll through it as it turns green, you save on accelerating back to speed. And don’t exceed the speed limit greatly. The slower you go it top gear, the better your gas mileage will be as long as you don’t lug the engine.

The engine uses NO gas if you are going downhill in gear, regardless of the RPM, as long as your foot is off the gas pedal. The computer shuts off the fuel injectors under these conditions.

If you shift to neutral the engine needs will get enough gas to maintain idle, which is more than none.

Keep the transmission in gear, follow the maintenance schedule, and keep the tires properly inflated.

In the city, you can stretch your fuel economy a lot, but you have to employ all kinds of dangerous driving habits. If you can afford the gasoline, take no action, just drive safely. If you shut the engine off and coast, you will save. It’s been proven. But will you not crash?