Is coasting in neutral bad

I noticed the other day my Qualcomm records time coasting out of gear .

 

I have driven 3 automatic equipped trucks. The first one didn't do that. But Volvo actually named it "Eco-roll". I don't know if its a good or bad thing. But if I hit the brakes, it just goes back into gear. Doesn't really seem to be an event that would be particularly damaging to the truck in any way. No bang, pop, lurch, jerk, or anything like that. Pretty smooth, actually.

 

It will not kick it out of gear like that if you're using the brakes or the engine retarder. So, I don't see it as being as dangerous as you do. On any hill you will actively need to slow down and control your speed, it doesnt engage.

 

You won't save any fuel coasting down the hill. When you hit the flat you'll save a bit by slowing at a lesser pace. That's where the eco-roll or whatever they call it comes into play I believe.

As mentioned previously the savings would be negligible.

 

I didn't see any improvement in fuel economy over earlier trucks I've driven. I wonder if some of this automation stuff isn't just a way to get us used to the truck eventually not needing us. It doesnt really need to achieve better mileage to do that. Its just the point of getting us to accept that the technology works and knows what its doing. Even if it doesn't. But I'm a pessimistic sort. So there probably isnt any anti-driver conspiracy afoot. And in a few years, eco-roll will be seen as a failed experiment, and will no longer be available.

 

As long as the engine is turning the transmission should get lubrication. I can't see a benefit to it fuel economy wise. With your foot off the throttle the engine is in a no fuel condition anyways.

 

Popular Mechanics magazine put out an article about this subject several years ago. When going into a slack situation, (downhill) the injectors stop getting fuel and the rotation of the driveline/ engine etc continues to keep the power going. It's all too complicated for me to understand but even leaving it in gear going down hill uses virtually no fuel.

As far as the DT12 AMT going into ECoast mode, not sure it is truly out of gear because when it gets 8-10 miles above certain killing speed it downshift 3 gears and applies full jakes and launches the driver through the windshield.
I have found it is just easier to run the stupid thing in Manual mode to control which gear and jake settings I like. But gosh golly gee whiz my left leg sure has nothing to do.

By the way I'm reporting you to the National Security Independent Thought Control Patrol Agency for thinking on your own to run your truck in neutral downhill. You are now on the Watchlist....

 

Coasting down hill does not turn injectors off.
The engine is still receiving idle fuel coasting with your foot off the throttle.
Here's an example why.
If it wasn't getting idle fuel when an automatic trans went in to echo coast the engine would sthall when it uncoupled from the engine.
Even everyday cars gets idle fuel when you take your foot off the throttle and coast.

 

The engine is getting fuel regardless or gear or no gear. Roughly .8 is burned idling when parked. Same theory when coasting down in neutral. Because the engine is idling.

CORRECT??????

I don't know about the out of gear vs. In gear. Does any of us know how the ecm software is programmed?????

But here's the big thing.

Get in an accident coasting down in neutral and guess what happens.

You failed to maintain control of your vehicle.

Also. How are you supposed to jake brake??????