Coasting a manual car - NOT downhill

Maintenance/Repairs
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21

I’m assuming OP is talking about slowing to a stop, and going 6th–>N–>3rd (after dropping a lot of speed). Or even 6th–>N–>1st, if OP has to stop for the light.

Completely safe! I suppose it’d be better, from a safety standpoint, to leave the clutch depressed while moving, to facilitate a “quick getaway” if needed, but that’ll just stir up a whole “throwout bearing” controversy, so I’ll stop at that.

And yes, I know that technically it is illegal in most states to coast your vehicle.

I humbly posit that “transient” neutral ops cannot be illegal, or every MT driver breaks the law every time s/he drives! Consider:

(1) No matter how one comes to a stop, at some point, one is moving too slow to prevent the engine from stalling, were it in gear. Thus, it is impossible to come to a stop, with the engine idling, without transient “coasting in neutral.”

(2) Unless one “speed shifts,” there is a split second in changing gears where one is “coasting in neutral.”

(3) And then there’s hybrids, many of which can be operated such that neither the engine nor motor are engaged while the vehicle is in motion. Yet, car co.s seem to have no trouble getting these “neutral-coasting” vehicles to pass Federal muster, as well as all 50 states.

Given that these 3 scenarios argue that “coasting in neutral” is (legal, necessary, and/or completely unenforceable) for “short” periods of time, what qualifies as “short”? My answer would be–absent legal precedent–“short” is whatever I need it to be.

22

I know this is no big deal, but it’s discussions like this that make it worthwhile not to buy a manual transmission in a used vehicle.

23

Your technique will not harm the car at all. If you use the tach to match wheel speed and motor speed so there is no lurching when you engage the clutch even better. The smoother the clutch engagement the less wear and tear on the clutch and trans.

I do the same thing you describe at times, but less frequently given the area I drive in. No harm, no foul, drive on and enjoy your car.

24

I think you are failing to make the distinction between shifting to neutral and taking your foot off the clutch, and simply holding the clutch down. Holding the clutch down while the transmission in gear isn’t considered “coasting” in the legal sense.

25

Why?

26

Agree! Match the engine speed to what it will be when the clutch pedal is out as best you can in whatever gear you select. A repeated gross mismatch during deceleration with engine speed starting at much less than after clutch engagement stresses trans bearings to where you could eventually need an overhaul. Engine speed higher prior to clutch engagement will not be a problem.

27

I think that would depend on how the law is written, and it would be entirely state-dependant. (As there is no “coasting in neutral” law in my fair Commonwealth, I can’t say from firsthand knowledge of any law.)

I’d not be surprised if “neutral” was legally defined as “the engine having no input on vehicle speed and/or vice versa.” I have a hard time imagining motor vehicle code caring about “clutch depressed/gear selected” vs. “clutch released/no gear selected.”

28

I for one will not knowingly (which we seldom do) buy a manual transmission from an experimenter. It’s still excessive throw out bearing usage over the life of a car along with clutch re engagement. Enough to give her a problem; absolutely not, but the next buyer beware of this and other dubious practices. They get treated with more respect around here and not second guessing the engineers that make them. I’m amazed by the retorts of, “read the manual” in other situations, but doesn’t seem to hold water here. Leave the car in the appropriate gear…it’s that simple, no neutral, no Mario Andretti (sp) game playing.

29

LimeLight:

It sounds like the speeds or conditions you’re coasting at are low enough to not put you or others at risk.

As others have noted, if you match the motor and wheel speed when you re-engage it in gear again, you’ll be fine.

Even if your shifting habit was harmful to your car, my view is it’s OK to help you understand the pros/cons for such a habit. But it’s your car and you’re free to drive and maintain it as you wish. I can’t be judgmental if it’s different than how I would do it or if it’s not a prescription for getting 200k miles from your car.