I coast to a stop in neutral.
Manual tranny - cruise to a stop or downshift?
- Thread starter VeeDubb
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"Personally, I coast until the engine slows to idle speed, and pull it into neutral at that point. I sit in neutral with the clutch out until it's time to go. "
This is also my general driving habit. But the issue is more complex considering different types of cars.
In my book a good driver almost never uses the brakes. In order to do this one must be looking as far ahead as you can see and anticipate the upcoming events. It is easier when you are in familiar territory. I try not to hold up traffic while doing this and I stay in the right hand lane. Generally speaking, this gives me the EPA rating highway gas economy while driving strictly in the city.
I have tried many ways to increase gas mileage. The egg under the accelerator pedal does not help. If I step on it the engine RPM immediately goes into the area of highest efficiency and believe it or not this does not result in less MPG - unless you are now going too fast for the next intersection and have to use your brakes. This takes the energy you just put into your car and blows it off as heat. There will be no waist if you do not use your brakes or slow down using your engine for braking.
Engine braking - there are more issues than wear and tear on various parts. Braking is dynamic. With minimal, soft braking the front and rear do about the same amount of work. With hard braking the front may end up doing all the braking. Some car brake systems can apply different amounts of braking to all 4 wheels. The accelerometer tells the system if you are in a turn and how hard you are braking and adjusts accordingly.
If you have front wheel drive and use the engine to brake then this my work. But do you have a locking differential? Is the engine braking applied evenly to the left and right side? For rear wheel engine braking the situation is usually bad as the front wheels generally need to do the most braking. And again, is the engine braking applied evenly to both rear wheels?
With front wheel drive the weight of the engine over the drive wheels is good for driving in the snow. But rear wheel drive is best for fast acceleration as the weight is transferred to the rear wheels. In extreme cases the front wheels may actually be lifted off the ground putting all the weight on the rear drive wheels.
Shifting gears is not for braking, that is what brakes are for and designed to do appropriately. You shift gears only to put the transmission in the appropriate gear you will use next to accelerate.
There are always exceptions, as with big trucks, but for general car use do not use the engine for braking. Braking is not the function of your engine.
If your are thinking of gas mileage for some reason, remember that by far the best way to get the most from your vehicle is look far ahead enough to drive without the need to use your brakes. Also, set up your car for better efficiency. I always use higher pressure than is usually recommended. This is true even in my sports cars.
Make sure your set up is correct for your driving and tires. With the “regular” cars I had in the past I frequently used a size or two wider tire. You have to toe them in more. I always put in more negative camber as I corner faster than most people.
As with choosing the correct oil, your driving and braking are both style and vehicle dependent. There is one best way to do it in your situation. But NEVER use your enigne for braking, use the brakes.
aehaas
This is also my general driving habit. But the issue is more complex considering different types of cars.
In my book a good driver almost never uses the brakes. In order to do this one must be looking as far ahead as you can see and anticipate the upcoming events. It is easier when you are in familiar territory. I try not to hold up traffic while doing this and I stay in the right hand lane. Generally speaking, this gives me the EPA rating highway gas economy while driving strictly in the city.
I have tried many ways to increase gas mileage. The egg under the accelerator pedal does not help. If I step on it the engine RPM immediately goes into the area of highest efficiency and believe it or not this does not result in less MPG - unless you are now going too fast for the next intersection and have to use your brakes. This takes the energy you just put into your car and blows it off as heat. There will be no waist if you do not use your brakes or slow down using your engine for braking.
Engine braking - there are more issues than wear and tear on various parts. Braking is dynamic. With minimal, soft braking the front and rear do about the same amount of work. With hard braking the front may end up doing all the braking. Some car brake systems can apply different amounts of braking to all 4 wheels. The accelerometer tells the system if you are in a turn and how hard you are braking and adjusts accordingly.
If you have front wheel drive and use the engine to brake then this my work. But do you have a locking differential? Is the engine braking applied evenly to the left and right side? For rear wheel engine braking the situation is usually bad as the front wheels generally need to do the most braking. And again, is the engine braking applied evenly to both rear wheels?
With front wheel drive the weight of the engine over the drive wheels is good for driving in the snow. But rear wheel drive is best for fast acceleration as the weight is transferred to the rear wheels. In extreme cases the front wheels may actually be lifted off the ground putting all the weight on the rear drive wheels.
Shifting gears is not for braking, that is what brakes are for and designed to do appropriately. You shift gears only to put the transmission in the appropriate gear you will use next to accelerate.
There are always exceptions, as with big trucks, but for general car use do not use the engine for braking. Braking is not the function of your engine.
If your are thinking of gas mileage for some reason, remember that by far the best way to get the most from your vehicle is look far ahead enough to drive without the need to use your brakes. Also, set up your car for better efficiency. I always use higher pressure than is usually recommended. This is true even in my sports cars.
Make sure your set up is correct for your driving and tires. With the “regular” cars I had in the past I frequently used a size or two wider tire. You have to toe them in more. I always put in more negative camber as I corner faster than most people.
As with choosing the correct oil, your driving and braking are both style and vehicle dependent. There is one best way to do it in your situation. But NEVER use your enigne for braking, use the brakes.
aehaas
AEHaas, that's generally good advice except for the never use the engine for braking.
Engine braking is always appropriate for maintaining speed on long downgrades, something you aren't challenged with in Florida.
Brakes are for changing speed, engine braking is for maintaining speed on downgrades.
Engine braking is always appropriate for maintaining speed on long downgrades, something you aren't challenged with in Florida.
Brakes are for changing speed, engine braking is for maintaining speed on downgrades.
Ahhhhhhhhh, you're using your engine as a brake every time you let off the gas, no matter what gear you're in. Coming down an 8 or 9% grade in the mountains, you better as ---- be downshifting like a madman or you'll overheat your brakes.
I believe the argument here is whether to use you engine or your brakes when making a stop.
Never covers a lot of circumstances.
You should never be coasting in neautral while driving, ever. You are not in control of the vehicle, if you need to get on the gas, you are not in gear, not a good practice.
Same thing for leaving it in say 4th or 5th gear when coming to a stop. If you are going 25 and need to get on it quick while you are in 5th gear, you are screwed. You match the gear selection with your vehicle speed at all times, when both accelerating, and stopping/slowing down.
Engine breaking is a good thing, and a good practice, espeacilly when going down hills.
Always downshift, and never hold the clutch in at a stop for long periods of time as well.
Same thing for leaving it in say 4th or 5th gear when coming to a stop. If you are going 25 and need to get on it quick while you are in 5th gear, you are screwed. You match the gear selection with your vehicle speed at all times, when both accelerating, and stopping/slowing down.
Engine breaking is a good thing, and a good practice, espeacilly when going down hills.
Always downshift, and never hold the clutch in at a stop for long periods of time as well.
Agree 100%
JHZR2
Staff member
I stay in gear until I hit about 1100 RPM, as above that with the throttle position at zero, the fuel flow is shut off.
Then I pull it out of gear, coasting in neutral to maintain momentum for as long as possible.
like anything, it is condition dependent. If there is a reasonable need to be able to accelerate out of harm's way, I stay like njcruiser reccomends, however, being in control of my situation, driving defensively, and being well aware of my surroundings tends to make that a rare requirement.
Like AEHaas, I tend to at least meet, if not exceed (geerally exceed by 3-4 MPG) older EPA highway numbers in mixed driving. Havent even taken to the hypermiling stuff, like shutting down at tops of bridges, excessive tire pressures, etc., some of these things indeed being unsafe.
JMH
Then I pull it out of gear, coasting in neutral to maintain momentum for as long as possible.
like anything, it is condition dependent. If there is a reasonable need to be able to accelerate out of harm's way, I stay like njcruiser reccomends, however, being in control of my situation, driving defensively, and being well aware of my surroundings tends to make that a rare requirement.
Like AEHaas, I tend to at least meet, if not exceed (geerally exceed by 3-4 MPG) older EPA highway numbers in mixed driving. Havent even taken to the hypermiling stuff, like shutting down at tops of bridges, excessive tire pressures, etc., some of these things indeed being unsafe.
JMH
Kestas
Staff member
It sounds like you drive under very stressful conditions on a daily basis.
It sounds like he never drives under other than very stressful conditions.
"There are always exceptions, as with big trucks, but for general car use do not use the engine for braking. Braking is not the function of your engine."
I think that 'big trucks' shoudl be ex[anded to include any vehicle that needs better control of speed when braking. The Allison tranny on the Chevy trucks seems to have a mode where it will use the engine for braking to keep the vehicle at a given speed on down hills, something handy when towing or with a big payload. Others with sticks just engine brake, sometimes using an exhaust brake if they have one.
I think that 'big trucks' shoudl be ex[anded to include any vehicle that needs better control of speed when braking. The Allison tranny on the Chevy trucks seems to have a mode where it will use the engine for braking to keep the vehicle at a given speed on down hills, something handy when towing or with a big payload. Others with sticks just engine brake, sometimes using an exhaust brake if they have one.
Some semi-trucks are very loud when they engine brake. Most likely the DOT has received complaints from local residents or businesses and they outlaw it. People who live near off-ramps hear it all the time and it does get old.
Because some trucks have exhaust brakes on them which are very loud.
"Like AEHaas, I tend to at least meet, if not exceed (generally exceed by 3-4 MPG) older EPA highway numbers in mixed driving. Haven't even taken to the hypermiling stuff, like shutting down at tops of bridges, excessive tire pressures, etc., some of these things indeed being unsafe."
Me too. And while just dabbling with some of the less extreme hypermiling techniques (mostly pacing traffic carefully, etc ...) I generally get around 40mpg in my '06 Civic ... a car with EPA numbers of 33-38.
Me too. And while just dabbling with some of the less extreme hypermiling techniques (mostly pacing traffic carefully, etc ...) I generally get around 40mpg in my '06 Civic ... a car with EPA numbers of 33-38.
I have a manual trans (5 speed) and I have ALWAYS downshifted to every light/stop sign. I'm at 106,000 miles atm.
I notice when going down a big hill with foot off gas - in gear ScanGuage II says I'm getting 170mpg... When I put tranny in neutral I get something like 250mpg.
However, coasting down hill out of gear = 23% engine Load. In gear coasting down hill engine load = 9%.
I wonder why Scanguage shows more MPG (quite a bit more) when coasting in neutral vs coasting in gear???
I notice when going down a big hill with foot off gas - in gear ScanGuage II says I'm getting 170mpg... When I put tranny in neutral I get something like 250mpg.
However, coasting down hill out of gear = 23% engine Load. In gear coasting down hill engine load = 9%.
I wonder why Scanguage shows more MPG (quite a bit more) when coasting in neutral vs coasting in gear???
Nice video.
Also, I hate to offer advice on how to drive over the internet. If you really want to learn how to drive your vehicle properly and safely under the most hazardous conditions on the highway, take a defensive driving course. I don't think you will regret it.
One other thing that I have been aware of since first obtaining my drivers license in Pa., most states have made coasting (especially downhill) illegal. Check your local driving manual before admitting to coasting and being involved in an accident.
Also, I hate to offer advice on how to drive over the internet. If you really want to learn how to drive your vehicle properly and safely under the most hazardous conditions on the highway, take a defensive driving course. I don't think you will regret it.
One other thing that I have been aware of since first obtaining my drivers license in Pa., most states have made coasting (especially downhill) illegal. Check your local driving manual before admitting to coasting and being involved in an accident.
Maybe because you're goung faster. LOL
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