Hello fellow box owners!

I'm here to bring up a topic battled over in various ways many times here, but in a fairly specific form.

In an effort to conserve gas in my Automatic xB lately i've been taking strategic opportunities to coast in neutral. Before u tell me I'm going to tear up my transmission, let me give a list of requirements I have in my mind before doing this.

In one of the following situations:
- A distance from a light that has just turned red
- Going down a long hill with a stop sign, red light, or big hill on other side of it

And if all of these conditions are met:
- I'll be coming to a full stop OR shifting back into drive at no more than 45/mph
- I'm dang sure i won't need a boost of power for safety (IE..i do it only when i'm not in packed traffic, dangerous situation, etc)
- Shifting back into drive can be timed well (i've found certain situations it takes nicer than others)

What are your thoughts on this? I've not met any resistance from my box yet. Following the above rules, the shifts in/out of drive are extremely smooth, allow me to use very low RPMs on many streets around here, and the engine/transmission give no feelings of pain when i shift back in wisely.

Am I smartly saving gas, or doing something stupid without knowing it? I've only been doing this the past 500 miles or so, and my box is just over 5000 miles.

 

You know i've heard of other people do it too and I decided to try it to see if its easy, if it simply "sounds" bad on my engine. I dont know enough about how a transmission works to know if it f***s anything up or not. id like to hear from someone who has more knowledge. id assume in a manual it is different than an auto. but I do this down REALLY long hills. in the 580 there are these long hills that last like a mile or more on every hill so at the peak of the hill i just drop to nuetral, stay in the slow lane and coast, I can probably coast at 80 cause its a big highway and im safe in the slow lane, when i reach the bottom ill slow down to maybe 60, pop it into drive again but dont gas it until I feel and see the RPMs catch up nice and smooth. it doesnt sound or feel bad, so I do it then, and I totally understand what you mean by meeting those conditions.

 

Exactly! You're doing the same concept as i! Waiting for the RPMs to catch up and just being cautious popping back in.

 

Should be no problem with trans, as long as you are not stressing it when shifting back into D. I usually shift into N when waiting at the light for long. I am really curious about gas savings when shifting between D and N when coasting though.

 

Hills might be different, but when coasting to a light, you can just take your foot off the gas.

 

there is no significant difference in rpms for me at a light in N or in drive.... i am not sure where the advantage would be though, your engine is still running, just not with your driveshaft (i think...).... maybe less stess on engine? idk, could be interesting!

 

I don't see how you would gain anything by putting it in neutral. When driving normally and you release pressure from the accelerator pedal don't the RPMs drop down to idle when you are coasting?

As for putting it in neutral at a stop light that helps by removing the load of turning the transmission. The biggest benefit I'm aware of is it helps keep the engine from heating up as fast at long lights particularly when the AC is on.

 

I don't think its any diffent when you did this for 500 did you see any changes in fuel ?

 

as far as i know, taking your foot off the accelerator = extremely little to no fuel going to the engine. so putting it in neutral just means the car's going to use fuel to keep itself idling... therefore defeating your purpose.

oh and for the record.. it does not matter how fast you're going. with an auto you can put it in neutral and back into drive all day and not hurt it. don't overanalyze too much, it's safe.

and also for the record, my box is manual

 

i have a 5spd but i was told never to do this. 1) because its illegal and 2) something about no transmission fluid is being pumped through when in N...but that could be wrong.

 

illegal? Never heard that before.

 

its illegal to take your car out of gear because in case of an emergency you couldn’t accelerate if need be.

 

Well that actually makes a lot of sense.

 

haha i know turning your car off while in motion is also illegal for the same reason.plus most cars will lose power steering and brakes and that could end badly

 

I think that you will see just as much benefit pulling into neutral as you would just taking your foot off the gas.

My RPMs aren't drastically different in drive or neutral while at idle.

If you're interested in MPG, there's a thread in Power about removing the snorkel on the stock box with a K&N. Supposedly, some of these guys are getting 40MPG.

 

The RPMs ARE different when coasting at 40mph in neutral, and coasting at 40mph in drive with foot off gas. This is where I figure the fuel savings come in. The box also coasts a much longer distance when in neutral. I'm doing it consistently for this whole tank of gas, and I'll let you guys know what my mileage ends up being!

As for the snorkel thing...tried it, got no MPG gain and lost some mid RPM power, a toyota guy told me it'd make no diff, so it's back on.

Edit: I do agree with those saying sitting at a red light in N saves no gas, though. The RPMs are the same at a full stop whether in N or D. I'm talking about when you're flying down a hill

 

the best thing to do if you want better MPG is get an xA other wise i would say just enjoy the car, dont put yourself and others at risk just to squeeze and extra 1 or 2mpg out of a tank.

 

I say for any gains that you might see, that it wouldn't be worth it due to the "danger issue"

For a 5sp I think its safer at least for me, because I can get it into gear faster, where as an automatic does have a delay and in an emergency situation it may cause a problem.

When I go into N I only do it because I don't want to keep my foot on the clutch.

 

Yeah, this is why I'm very cautious about when I do it. One of the conditions I do it under is when there are large number of no cars around, no upcoming situations where I'd need to haul butt out of there, etc.

I mainly started this thread to see if I was silently killing my xB, or if not much harm is done. I haven't done it seriously for a full tank yet (am this tank), so MPG is up in the air for me.

 

See what happens, but yea, you're kinda letting your guard down when you're in neutral (same reason I don't like cruise control)

I enjoy driving my car. I personally dislike trying to roll like a granny to squeeze that extra 50 miles out of a tank. Sure, I may only get 23 MPG in my box, but I have fun driving it.

Either way, if you're going to be doing this as a routine, make sure your hand stays on the shifter to pop it back up immediately if need be.