[Christ]

Originally Posted by Thymeclock

True. I shift into neutral at virtually every red light I'm waiting at, then put it back into drive when the light changes. Why? because it takes a load off the A/T, and thus it generates less heat.

But I don't understand why you are downshifting an automatic. I can understand how it will provide braking (and save your brakes to some small degree) but how will it save gas? If the downshifted engine is braking the car more, it will be coasting less.

There are times when you'll need to stop or slow faster than coasting in neutral would allow. It's the next best thing, especially if your vehicle has DFCO.

As far as normal driving, I downshift to provide engine braking on hills, and that's about it. If you're in hilly terrain, it's not to save fuel, it's to save your transmission. Each shift creates clutch wear and fluid shear which heats the transmission more, and that's bad, so you downshift to keep the transmission from shifting up and down all the time. It could also save fuel in some cases, because upshifting and downshifting are fairly inefficient, and being in a lower gear, even with higher RPMs/less load, you might still use less fuel in some cases.