Any Mechanics Out There

[garyspence84]

Iv been having a discussion with a friend over driving. He knocks his motor into neutral all the time "to save on petrol". Which yes, I know it will do to a certain extent. But I thought that it would do damage to the gear box, he said it won't, but I'm not too sure.

Anyone?

G

 

[clay]

It is alway harder on gears and especially the motor if you shift while moving.

 

[StandbySetting]

Your friend is an idiot, coasting in neutral wastes fuel; And is also detrimental as you don't get engine braking. Moving under the inertia of the car with your foot off the gas saves petrol as the fuel injectors turn virtually off (just enough to keep the engine running), in neutral this doesn't happen. As for damaging the gear box, I'm unsure but I wouldn't have thought so, though I guess if he's shifting unnecessarily he might cause parts to wear out more quickly.

 

[dh058977]

Coasting in neutral in a modern car would use more fuel than braking in the conventional way. Your friend is using more petrol not saving it! However, to answer your question, in a manual car it will do no harm apart from more wear perhaps?! lol

 

[BLACK DDOG]

It's illegal, you are not in complete control of the car, points on you licence and a heavy fine.

 

[garyspence84]

Cool, cheers guys. That settles it for me

Never knew that it would use MORE fuel right enough, but there you go.

I will b continuing this debate tomorrow in work, I will pass on my new found knowledge on "the motor engine".

Cheers again

G

 

[Tolak]

It's illegal, you are not in complete control of the car, points on you licence and a heavy fine.

That would make double clutching illegal, something that is necessary for shifting heavier trucks with unsynchronized transmissions. You might save a slight bit of fuel with a carbureted engine, any monetary savings would be lost by increased wear on the brakes rather than letting the engine do the braking.

 

[BLACK DDOG]

It's illegal, you are not in complete control of the car, points on you licence and a heavy fine.

That would make double clutching illegal, something that is necessary for shifting heavier trucks with unsynchronized transmissions. You might save a slight bit of fuel with a carbureted engine, any monetary savings would be lost by increased wear on the brakes rather than letting the engine do the braking.

"Hold on" your driving rules there in the USA are different from ours in the UK.

 

[Ps3Steveo]

If in gear and going down hill and about to coast, to save fuel you need to leave it in highest gear say 5th or 6th and keep the clutch up as if it is in gear and the revs are decreasing as you go down hill the engine uses next to no fuel, coasting is a bad idea.

 

[Aquascaper]

Whilst being technically illegal it is highly unlikely that a police officer could determine whether you are coasting or not unless you roll past them at speed with no engine revs so it is almost unheard of for a prosecution to be made. It would fall under 'driving without due care and attention' and a charge would only be made with concrete evidence otherwise it would not hold up in court.

 

[Zenki]

O_O I'm shocked,I think yall need to stick to fish lol.


Coasting in neutral in a 5 speed is fine,you do it everytime you stop by pushing the clutch pedal down.

Coasting in neutral in a auto is a whole different story, it can damage the trans in the long run as you are really only supposed to change gears at a dead stop, neutral is more an emergency thing on autos.


As far as saving gas nope, no more than just taking your foot off the gas in a automatic.

now with a 5 speed it does save gas only if you are stoping and only if your like me and you "engine brake" as your motor will dump alot of excess fuel trying to adjust to the gear. Not noticeable on an unmodified car, although it happens still, but with a car like mine heavily modded with a timing advance,no cat,no emissions,and running on 93 octane or better only. you will notice that excess in the form of fireballs out the tail pipe

 

[Ps3Steveo]

You don't coast every time you stop, you stop the engine from stalling, that's not coasting, we're talking about coasting on a main road at over 30.