How to get the most mpg out of a 5-speed?

May 20, 2007 9:39 AM

How do you drive a 5-speed for better gas mileage?

When I tell people that I am buying a car with a manual transmission, they often say something like, "Oh, that'll get great gas mileage - as long as you drive it right." These conversations are usually brief enough that I don't think to ask, "Hey, wait. How, exactly?"

How, exactly?

posted by ramenopres to travel & transportation (30 answers total)

Basically, don't be aggressive and keep the revs below 3000 rpm.

There's a lot of more specific advice in this thread from the StandardShift.com forums.
posted by IvyMike at 9:49 AM on May 20, 2007

The trick is keeping the RPMs in the right range. It sort of differs from car to car, but a lot more gas gets used if you're revving it too high (VRRMM! VRRRM!) or too low (put put put put...). Maintaining good manual mileage is all about watching the tachometer like a hawk. Find the sweet spot, the spot where the car makes very little noise but isn't starting to die, and stick to it.
posted by koeselitz at 9:50 AM on May 20, 2007

It used to be that automatics were much worse mileage-wise, and a lot of people still think that's the case. But with advances in transmissions, they may have the same mileage, or the automatic may even be better. A 2007 Honda Civic gets 40 mpg highway on the automatic and 38 mpg on the manual.
posted by smackfu at 9:52 AM on May 20, 2007

Getting into the highest gear you can, at the lowest possible speed, will save you plenty of gas.

Why? Because you use less gas when the engine is turning slowly. The slower the engine turns, the fewer the number of explosions in the cylinders. And fewer explosions means less gas consumed.

So, if you drive a manual transmission car, shift sooner. As long as the engine doesn't buck, shudder, or ping, you're fine. You'll sacrifice the ability to accelerate quickly — but you can always downshift if you need to accelerate.

Your owner’s manual will give you further information on when you should shift. It should give tell you what gear you should be using for each speed range.
posted by dnthomps at 9:54 AM on May 20, 2007

Many cars are tuned to get the best gas mileage between ~40 and ~60mph. Exceed those speeds, and mileage drops dramatically.

Here in ND, the interstate speed limit went up to 75mph. The 189 mile trip to my parent's house takes 3/4 of a tank of gas if I travel 65, and an entire tank of gas if I travel @ 75mph. For my little car, it is a steep curve.
posted by fake at 9:58 AM on May 20, 2007

The classic advice on extending gas mileage with a stick transmission is to imagine that there is a raw egg taped to the bottom of your right foot, and drive so as to keep that egg intact. No fast acceleration, no hard braking, thinking ahead to plan shifts, using engine braking and early downshifting to control speed down grades, keeping the car well balanced in curves by slowing as necessary entirely before entering the curve so as to be able to accelerate lightly and smoothly through the curve to its exit, and putting the transmission in neutral at stop signs are all good ways to keep the egg unbroken, too.
posted by paulsc at 10:25 AM on May 20, 2007

Drive like your grandma would, unless she is the little old lady from Pasedena, or as my driving instructor taught us years ago, just pretend there is an egg under your shoe. Don't break it.

It's true that the advantage of a stick over an auto are far smaller these days as most cars have a locking differential that makes a mechanical connection just like a clutch once you get to highway speeds. In the old days it was always a fluid connection with an attendent loss in efficiency. Add in the fun of accelerating a stick through the gears, even an econo stick and most people are better off with an auto.
posted by caddis at 10:43 AM on May 20, 2007

basically ... learn to change gears ... drive the car at the correct rev range ... don't lug it and don't over-rev it (meaning don't be in a hurry to get into top gear) ... and learn to brake with your gears/engine. Advanced drivers match their revs when they shift ... ie when shifting down they blip the engine ... but this is not so important since the wide use of syncromesh in ... ohhh ... the 50's.

Good advice is to drive gently, keep your tyres at the suggested air pressure and have them balanced, learn to check your oil and water levels (inc. the battery water levels). Wash and clean your car monthly (keeps the resale value up there and is good advance warning of problems) and wash that engine (after bagging the electrical components) ... check all your lights at the same time. Get it serviced ... let me repeat that ... GET IT SERVICED regularly.

But, as has been mentioned above, the modern auto gearbox is pretty efficient ... there are no significant benefits to be had for mileage (but the breaking can save your arse in an emergency) and chicks dig guys who drive manual.
posted by jannw at 10:46 AM on May 20, 2007

Getting into the highest gear you can, at the lowest possible speed, will save you plenty of gas.

Not in the long run. It can be bad for your engine, because it's working too hard to drive the wheels.
posted by weapons-grade pandemonium at 10:49 AM on May 20, 2007

make sure it's in 5 when driving down the highway and cruising at highway speeds, five is sometimes known as overdrive, as on my old ford ranger
posted by Salvatorparadise at 11:55 AM on May 20, 2007

Remember that the 5th gear is your money-saver. It's whole purpose is to save gas. Get there as quick as possible, and stay there as much as you can. However, try not to go over 2500 RPMs. If you are pressing the gas pedal down "too much" (very subjective), down shift to get more power with less fuel.

It used to be that automatics were much worse mileage-wise, and a lot of people still think that's the case.

Vile, evil propaganda!! =)
posted by triolus at 11:56 AM on May 20, 2007

I usually drive by ear. I figure, the less noise the engine is making, the less energy is being wasted (on sound as well as, probably, heat).
posted by amtho at 12:11 PM on May 20, 2007

and chicks dig guys who drive manual.

:) But do guys dig chicks who drive manual?
posted by ramenopres at 12:13 PM on May 20, 2007

yes
posted by sophist at 12:52 PM on May 20, 2007

Agreed.
posted by hutta at 1:56 PM on May 20, 2007

"and learn to brake with your gears/engine."

How would engine braking INCREASE efficiency? I would think idle would use less gas than engine braking.
posted by SirStan at 2:15 PM on May 20, 2007

In addition, with modern cars, you use more gas when the clutch is in (ie the engine disengaged), than you do with your foot off the gas but the car still in gear (such you might do when coasting up to a stop light). This is because computer-controlled engines will cut the gas off completely when the wheels are turning the engine rather than of the engine turning the wheels, whereas once it's in neutral, or when the clutch is in, the engine requires fuel to idle.
posted by -harlequin- at 2:27 PM on May 20, 2007

The above bit about saving gas by having the engine in gear - I suggest using it in situations where you don't need to change gears. If you need to change gears in order to engage the motor with no gas, it wouldn't surprise me if you lose as much (or more) in wear and tear than you save in gas. I really have no idea how where that cost/benefit line is, but if no shifting is needed - merely taking your foot off the gas suffices, then it's a moot point, and you might as well not use the clutch until you have to.
posted by -harlequin- at 2:33 PM on May 20, 2007

All modern fuel injected cars have decel fuel-cut, which means you use zero gas when coasting with your foot off the gas, as long as the engine is engaged, i.e. you do not have the clutch depressed. If you engage the cluth, then now you have to burn gas idling the engine because the wheels no longer keep it turning on its own.

This is a long way of saying that "take it out of gear while coasting to save gas" is a load of BS.
posted by Rhomboid at 2:55 PM on May 20, 2007

Oops, and now I see I've committed the crime of duplicating what the last guy said almost verbatim.
posted by Rhomboid at 2:56 PM on May 20, 2007

and chicks dig guys who drive manual.

Let's be honest here. Guys dig guys who drive manual, and chicks don't care. The same thing as fast cars.
posted by smackfu at 3:14 PM on May 20, 2007

Errrm sorry smackfu ... chicks who drive manual really dig guys that do the same, imho (and most people here who are serious about driving... you know the rest). If the car happens to be spending weekends at Watkins Glen, all the better.
posted by vers at 4:20 PM on May 20, 2007

All modern fuel injected cars have decel fuel-cut, which means you use zero gas when coasting with your foot off the gas, as long as the engine is engaged, i.e. you do not have the clutch depressed. If you engage the cluth, then now you have to burn gas idling the engine because the wheels no longer keep it turning on its own.


Wtf? Engine engaged=burning gas.
posted by lalochezia at 4:33 PM on May 20, 2007

No. Engine engaged + fuel cutout activated = burning NO gas. Engine disengaged = fuel cutout not activated.

That said, it's still possible to save fuel by coasting down hills with the engine disengaged, because idling actually uses very little fuel, and the speed you pick up coasting down hill can save you fuel once you've got to the end; if the engine is engaged without fuel, it acts as a bit of a brake and you won't pick up as much speed.
posted by flabdablet at 6:05 PM on May 20, 2007

lalochezia, fuel is injected into the cylinders by electronically controlled injectors, which are entirely under control of the computer/ECU. When it detects that you've taken your foot off the gas and are coasting, it turns the injectors off entirely. Zero flow. The engine continues to rotate because of the sizeable mass and momentum of the car.
posted by Rhomboid at 7:44 PM on May 20, 2007

chicks dig guys who drive manual.

As a chick, let me weigh in that I dig anyone who drives manual. I grew up in Vermont, where an automatic not only made you seem lazy, but stupid in terms of long-term survival strategy.
posted by grapefruitmoon at 10:11 PM on May 20, 2007

On modern vehicles, you aren't going to save any significant amount of fuel cruising on the highway in a standard rather than an automatic. Where you will see savings is in the city if you do as others above have suggested: accelerate slowly, keeping the revs down, coast (in gear) up to stop lights, get the car into a higher gear if you are going to be going a while without needing to accelerate, plan your shifts ahead for hills, corners, and stoplights, and engine brake or coast on the downhills as required.

However, there is much more of a difference in fuel consumption between a car driven for fuel economy and a car driven without care, than there is between a manual and a automatic, so the most important thing is to drive at reasonable speed on the highway, keep your tires well inflated and your engine in good repair, and keep your foot light on the gas and off the brake.
posted by ssg at 10:17 PM on May 20, 2007

And I don't care if chicks dig that I drive manual, but I certainly dig driving a manual myself and encourage everyone to drive a manual if they dig it (and to try it a few more times if they think they don't).
posted by ssg at 10:20 PM on May 20, 2007

Driving manual is great. You'll be bored with automatics once you start. I think there's some common mental ground amongst manual drivers-- we like to be in control, efficient, and effective. I'm not sure about the chick diggage factor, but I know that any stick shifter will respect another stick shifter a little more because of it. Plus, one day you may have to drive someone else's manual-transmission car in an emergency.

As far as MPG: work with the road. Use downhills to your advantage - either coast or shift into 5th. Avoid having to accelerate uphill. Follow the eggshell rule, especially for turns. Coast up slowly to red lights instead of riding the gas and then braking at the last minute. Remember, unless you drive a hybrid, braking represents wasted energy. In traffic jams, leave a really big gap in front of you to avoid dancing between gas and brake.

Then use the gas you saved, go to an empty road and take it to to the redline.
posted by scose at 12:01 AM on May 21, 2007

If you're keeping the engine around 2500-3000 RPMs in a 4 cylinder, naturally aspirated engine, you'll probably put far more stress on your engine. If you're driving a V8 and you shift at 6000 RPM, however, you'll be half deaf and burning tons of gas while rapidly gaining speed. Good guesses are 2500 for a V8, 3000+ for a v6, and ~4000 for a 4. This will vary from car to car.

Smaller engines have far less torque, and they operate far more efficiently at faster speeds. After you've started speeding up, you'll notice the gas pedal becoming far more sensitive. That's the power band, and that's where the car operates best, but not most efficiently. Somewhere in there will be your shift point.

Although, i wouldn't advise tapping the gas pedal to test this out. You'll do that annoying jerky thing, which is horrible for your car and makes you look like a moron to those chicks who dig guys who drive auto.
posted by onedarkride at 5:13 AM on May 21, 2007