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View Full Version : Wisdom of shifting into neutral without using the clutch (2008 Corolla)


run2w8s
01-29-2008, 11:04 PM
Planning to pickup my new Corolla tomorrow :) and was wondering about shifting. My first car 32 years ago was a 3 speed on the floor but have not owned a manual since then. (not counting a long string of motorcycles)

Have seen several references on other websites about shifting into neutral without pushing in the clutch pedal. This would make transitioning from a pulse to a glide a bit easier. Please limit your advice to what you are pretty sure about. (not a guess or feeling)

If you do condone clutchless shift into neutral, what is your recommended technique. (for example: let off the accelerator at the end of a pulse and gently move the shifter to neutral while coasting.)

With my automatic, I restart with the key and rev match before shifting back into drive. What is a good technique for bump starting at the end of a glide with a manual?

PS: have managed to average over 35 mpg in the 1998 Accord Automatic over the last 8,000 miles. :p Really want to maximize the 5 speed Corolla's MPG, so any other advice is welcome.

Thanks for all the help, sure am enjoying the hypermiling lifestyle.

Jeff

koreberg
01-29-2008, 11:59 PM
Shifting into neutral should cause no issues, provided you let the engine unload from the transmission before you try to move it into neutral. It should only require a light touch. If you need more than a light touch you're not doing it right and causing damage.

Shifting up or down from neutral requires speed matching. Its all do able without causing damage to the transmission. Upshifting is easier than downshifting neither is impossible to do, but messing up will cause damage to your engine.

As far as bumpstarting of course you need to use a clutch for that, Typically I bump start and then clutch straight away and rev match before I shift into the correct gear. I do not know how it would work to bumpstart and then go straight to neutral without using the clutch.

I would not suggest driving without using the clutch but i'm not going to say it can't be done. I would say that the syncros can speed match properly a much higher percentage of the time than most drivers could.

2TonJellyBean
01-30-2008, 08:29 AM
Just be careful because if you get too cavalier about shifting into neutral without the clutch and then you do that some time with the cruise control engaged, your engine is going to rev higher and higher until you touch the brake, clutch or cruise cancel.

shifty35
01-30-2008, 08:56 AM
I see no problems with shifting into neutral w/o the clutch. I've ran all the way up through the gears without touching the clutch just to show people it can be done. Unloading the engine first is a good idea just to prevent it from revving when the transmission disengages from the wheels.

run2w8s
01-30-2008, 12:31 PM
Thanks guys.

Let's make sure we have a common understanding.
When you say "let the engine unload from the transmission", do you mean lifting off the accelerator pedal before shifting to neutral without pushing the clutch pedal?

When I referred to bump starting(which may be the wrong words), I meant coasting in neutral, push in clutch pedal, shift from neutral to the desired gear (5th on the highway), let out clutch to restart engine, press accelerator to pulse to the desired top speed. When you say "bump start and then clutch straight away and rev match before I shift into the correct gear" it sounds like you are doing something very different. Perhaps a detailed description of what you are doing/recommending would be helpful.

If anyone else has a recommendation, please chime in. (especially about transitioning between pulse and glide with a manual transmission.)

shifty35
01-30-2008, 01:03 PM
"Unload the transmission" does mean release the accelerator before pulling out of gear.

Some people use the "bump" from the bump start just to get the engine spinning - then you immediately push the clutch back in, rev match with the accelerator, and release the clutch again to accelerate.

I personally see no need as once you bump start the engine, releasing and reengaging the clutch will just wear it more. Once it grabs enough to start the engine, it's not going to slip / wear much more.

koreberg
01-30-2008, 01:17 PM
I Usually bump start in 5th, reguardless of speed, a lot of the time i'm not going fast enough to continue driving in 5th after bumpstarting so I reclutch, revmatch to the correct gear and shift. If I am at the right speed for 5th then I do not reclutch.

jcp123
01-30-2008, 01:27 PM
I shift clutchless in my car fairly routinely, both up and down. As I don't grind (usually), I don't think there's too much harm in doing it - it's doing the same thing as it would be if yo uclutched it, only your right foot is doing the rev matching instead of the transmission's internal synchronizers. It just takes some practice to match the revs, and it helps if the car has a tach.

Just remember, if you can't find 'em, grind 'em! :D

PaleMelanesian
01-30-2008, 01:53 PM
I bump-start like this:
- Clutch in, choose top gear, or 4th if below ~15mph
- Clutch up-down quickly, just enough to fire the engine
- Choose gear, rev-match, release clutch, pulse

Step 2 is really light and smooth, and makes no jolt or jerk at all. I feel it gives less wear on the clutch, too, but I don't have any proof of that. Passengers appreciate it, though. Sometimes they don't even notice. ;)

Right Lane Cruiser
01-30-2008, 02:53 PM
That is my procedure too, Andrew. If you just "drop" the clutch you get quite a jolt at most speeds.

shifty35
01-30-2008, 03:04 PM
I too have a "passenger-friendly" style that is a lot different than my high-FE escapades during my commute. :)

Intense
03-26-2008, 02:45 AM
This is what I do and it does nothing bad to your transmission.

Say you are slowing for an upcoming light in third gear... lift off gas pedal, tap gas lightly and quickly and then immediately pull the shifter into neutral. It essentially loads and then unloads the transmission (bounces) and you are grabbing it right when there is really no load on the gears. Works great- been doing it in my car for over 30k miles.

diamondlarry
03-26-2008, 05:08 AM
To shift out of gear with out the clutch, I usually put a slight pressure on the shifter then let off the gas pedal. As soon as I let off the pedal it takes the load off the transmission and it slips out of gear very smoothly. As for bump starting, I too use the method where as soon as the engine fires, I stick the clutch back in and choose the proper gear for the speed I'm going. On my Saturn I used 5th to bumpstart unless I was at or below 10 mph. I once had a passenger with me that never knew I was FAS'ing and bumpstarting until I told him. Since I had a FAS switch, they never saw me kill the engine and my bumpstart was smooth enough that they never noticed.

Homeboymi
12-15-2008, 03:08 PM
Hey,
I am new here and thought I would add my 2 cents to this thread. I have bumped my 93 Cavalier 5 speed into neutral without the clutch for 15 years and 200,000 miles as I approach a stop. No problems. Didn't hurt the engine, transmission and it still has the original clutch. I leave it in neutral until I am ready to continue. I tried bumping it into neutral coasting down hills using the brakes. No good! I warped the brake rotors coming down Palamar Mountain! Now I use my transmission to slow down instead of the brakes.
Am I getting better MPG slowing down with the transmission or bumping it into neutral and slowing down with the brakes?

Right Lane Cruiser
12-15-2008, 04:07 PM
Depends upon whether or not your car has DFCO (Deceleration Fuel Cut Off) -- that feature turns off the injectors when you are using engine braking and the RPM is above 1100 or so. If your car does have this feature you won't be using any fuel at all when engine braking.

Kyo
12-21-2008, 03:09 AM
Most of my clutch experience is with a rotary engine, you can hear when the transmission is not loaded, since, you can hear when the engine is quiet. Engine breaking produces a bit of sound from the exhaust and acceleration/slight load produces exhaust noise, of course. So, I would find the sweet spot in between a depressed pedal and completely letting go, that 'silent' spot, where there is no load, and, you should be able to lightly press/pull with your little finger and the shifter will slide out of gear, any resistance and you have a load.

Now, that was a rev happy engine, but I did this with all my other standard transmission cars, though they didn't communicate with me as well through the aural spectrum :) I also begun shifted without clutch once I became very familiar with my car at various speeds, where the sound and visual speed were second nature and you don't have to look at the speedo/tach to accomplish it. Not recommended though, since you can tear up synchros and grind gears for no reason if you make a mistake.

Have fun with your new car :)

Shrek
12-22-2008, 03:41 AM
Hey,
I am new here and thought I would add my 2 cents to this thread. I have bumped my 93 Cavalier 5 speed into neutral without the clutch for 15 years and 200,000 miles as I approach a stop. No problems. Didn't hurt the engine, transmission and it still has the original clutch. I leave it in neutral until I am ready to continue. I tried bumping it into neutral coasting down hills using the brakes. No good! I warped the brake rotors coming down Palamar Mountain! Now I use my transmission to slow down instead of the brakes.
Am I getting better MPG slowing down with the transmission or bumping it into neutral and slowing down with the brakes?

You probably did not warp them, just at some point you came to a stop with the extremely hot brake pads firmly pushed against the rotors. Doing this leaves an imprint on the rotors that will cause the familiar 'thumpthumpthump' braking that is always signed off as warped rotors by dealers.

Just my 5 cents :)

Shrek
12-22-2008, 03:45 AM
Be sure to learn and have fun with both your corollas fuel cut and VVT-i system.

You can learn a bit about how the VVT-i operates by feeling how the fuel-cut seems to brake the car heavier at the end, just before the fuel-cut cancels. This is the vvt-i system changing the cam phase at low rpm (vvt-i is operative at engine start, and in an rpm-range that I do not fully understand yet, but at 1500 rpm it is active, and at 1100 rpm it is not)

slichopshop
12-27-2008, 05:00 PM
hello,

I used this method on an older chevy s10 pickup and eventually wore out the sycro's ,,,
then it would have the problem of jumping out of drive gears when you least expected it

i am sure new toyota is different than older chevy s10

but

my word would be caution

tranny repair is not worth the cost of saving time/fuel rather than fully pressing in the clutch

and regarding toyota -- thanks to daughter using wifes toyota pickup
i also know from experience that not pressing in clutch fully when shifting wears out gears and leave shredded mess in tranny case

Good Luck
john

jimepting
12-27-2008, 07:13 PM
Yes, just lift the accelerator and "feel" the easy push into neutral. I'm quite a critic of synchronizer abuse, but I see not technical harm in doing this.

In my mind, it is quite a "wash" as to which restart technique minimizes wear, with the exception of "clutchless" gear engagement, which requires considerable skill to avoid crunches, and severe synchronizer/dog clutch wear. It is "probably" best to clutch and engage a higher gear. Once engaged, after the bump you may as well leave it there if there is an appropriate match. For rev matching to matter at all, it must be done with the clutch out. Otherwise you aren't spinning the parts up to sync speeds. So you may want to learn double clutching techniques if you want to do any rev matching.

jimepting
12-27-2008, 07:17 PM
OBTW, the clutch takes quite a beating with bump starting, particularly if taken to the extreme. If you do it gently, the cluthc disc is slipping for a relatively long time. If you do it abruptly, the cluth pressure plate takes the brunt of the abuse. Don't think that this practice is without consequences, though some clutches may be rugged enough to put up with it for a long, long time.

Stormtrooper06
12-27-2008, 08:27 PM
thats what I'm thinking.
The upsides to doing this can be quickly hushhhhhed if on false slip of the foot/hand takes place.

Even after reading all this, I have the premis of it all , but really its best understood when someone teaches you it in person (preferably on there car first, then trying it on your car if you are up to it).

Sulfuric
01-05-2009, 09:00 PM
Here's my post from ecomodder:

http://ecomodder.com/forum/showthread.php/messed-up-clutch-start-possible-problem-6661.html

I ran into a small problem after messing up a clutch start yesterday, didnt feel like starting a new thread(sorry if i hijack!)



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