How to Get Better Gas Mileage with a Standard Transmission
Gas prices have been over $3 per gallon for quite some time now, and it wouldn’t surprise me if it stayed there for ever. Spending less money on gas is something we would all like to do. That’s why sales of economy cars are up. That’s why the first Kia Soul we looked at was sold to someone else while we were sitting inside discussing financing! We ended up getting the next one they got in. That’s an easy step to saving on gas: driving a more fuel efficient car.
But is that it? Isn’t there something else we can do?
When I was younger, I remember hearing that driving a manual transmission (i.e. a “standard”) would get you better gas mileage. I alwas took that for granted. But more recently, I’ve been hearing it’s no longer true. When looking at the information on new cars, many of them list the same, if not better, MPGs for their automatic transmissions. The logical side of me doesn’t understand, because an attentive driver knows more about the road ahead than any automatic transmission. The cynical side of me thinks that they want to sell more upgrades to automatic, so their test drivers’ feet have a bit more "lead" on the standards.
Maybe there’s more to it on some of these cars, but whatever the reason, it may not always be true. Consumer Reports actually tested the theory, and showed that manual transmissions more often get better MPGs. And in personal experience, I have always gotten MPGs that exceeded the EPA’s estimates. The 2011 Kia Soul gets an EPA-estimated MPG of 26 city, 31 highway, with an overall average somewhere in between. My own personal overall average so far, according to the ‘ave MPG’ reading on the console, is over 34 miles per gallon!
I’ve been driving a standard/manual transmission for years. A standard gives you more control over what the engine is doing; an automatic takes that control away. Here are some of the ways I try to maximize my gas mileage with that control.
Lighten the Load
It may seem obvious, but having less weight in your car will improve your gas mileage. If you carry around a lot of stuff (or people) regularly, it’ll cost you more.
Turn off the A/C
Running the air conditioning makes the engine work harder, and reduces gas mileage. Since I live in the northeastern US, there are relatively few days throughout the year that are too hot for just windows. This may not be practical in hotter climates, but it’s worth thinking about it on days that are bearable.
Another factor here is how much highway driving you do. Although air conditioning reduces gas mileage, open windows at higher speeds can produce drag, which also reduces gas mileage. So, on the highway, it’s a bit of a judgement call.
The greatest advantage you have over an automatic transmission is that you can see what lies ahead. You know where the road leads, and you know what you will need from the engine in order to drive over it. One of the ways you can take advantage of this is by pushing in the clutch and coasting:
- When approaching a stop sign or red light, you may be able to push in the clutch and coast for a significant distance. If you’re on a flat road, maybe ¼ mile. If downhill, even slightly, maybe indefinitely!
- If you’re on a slight decline, you may be able to coast and still maintain your current speed. No sense in using the engine if it’s not needed.
Get the Lead Out (of your foot)
Slower acceleration uses less gas. But sometimes it’s tough to get used to slower acceleration, especially if you’re used to driving, or ARE driving, a car with a lot of power. Accelerating is fun! My suggestion in this case is to do it in moderation. Instead of racing off the line every time, maybe accelerate quickly only once out of every three times, accelerating at a moderate pace the rest of the time.
Use the Highest Gear for the Road Ahead
Lower RPMs means less gas is being used. If you have 5 speeds on your car (not counting reverse), use 5th gear as often as possible.
This seems simple, but it can actually take some time to get it right. Obviously, you’ll use 5th gear on the highway going 65mph. But what about a suburban road, going 35mph? Then the question becomes, “how much torque/power do you need?”. If it’s steady going, few slow downs or speed ups, and no steep inclines, then 5th gear may be enough to simply maintain your speed.
But if anything changes, you’ll be downshifting. Every car is different. My Kia Soul can do the above easily. But any slower than 35 is usually too slow for 5th gear, and the RPMs get too low and the car will rumble (ever accidentally go into 5th instead of 3rd?). And So, once you’re familiar with your car, you can choose the appropriate gear for the speed and the road.
DON’T Downshift to Slow Down
It is VERY common for people who drive standard to use downshifting as a way to slow down. Truckers do this all the time. But I’m not talking about trucks. There are times for doing it, but those are few and far between. The reason people do it usually comes down to preserving their brakes. But a wise man once said: “brakes are cheaper than a clutch”. But NOT doing it may actually save you gas! Downshifting forces your RPMs up. And if the engind is running faster, then more gas is being consumed, just to keep up, even if you’re foot’s not on the gas pedal. With the clutch in, the engine is idling, which is using as little gas as possible.
There are some very good reason to downshift:
- You’re on a long steady decline. Riding the breaks for a long time can heat them up too much and cause warping in the rotors. So, in this situation, it often makes sense to allow the engine to assist the breaks.
- Acceleration is needed. You won’t get much out of 5th gear, and trying to push it without downshifting won’t save you anything.
Use the “avg MPG” readout
If your car has a setting to show the average MPGs, it can be very helpful to leave it there. There are so many little intricacies to driving, and to driving a standard, that the only way you’ll ever really know what works and what doesn’t, it to experiment and see it for yourself. Reset the average at every full tank (to start), try not to pay so much attention to it that you get into an accident, and allow it to be your little reminder against falling back into bad, gas guzzling habits.
- Fuel economy test manual vs automatic transmission
Consumer Reports tests fuel economy between manual and automatic transmissions for this report and video.
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