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Comment by Salgat | Hacker News Reader

I ended up going back to automatic after 3 years of manual. Automatic is more fuel efficient, more convenient, and honestly I can't enjoy urban traffic either way, at least with automatic I don't have to think about it. If I truly want to enjoy a manual I'll do it on the race track.

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As a cyclist, I fear that indeed, automatic requires less thinking, thus less concentration.

Are there studies on the frequencies of accidents based on manual vs. automatic?

I would be very interested in such a study.

I have driven both autos and manuals and have noticed a distinct difference in focus when driving the latter. I feel more engaged with the roads and my environment. I also noticed that I've never fought to stay awake while driving a manual, and unfortunately this is the case with automatics.

My previous and current cars are manuals, and I don't ever plan on buying an auto in the future. If my next car has to be a Miata or something, so be it.

I always feel like the fighting to stay awake feeling is a consequence of the road, like a long boring highway. In this case, how is a manual any different than a automatic, being that you are in the highest gear and driving without needing to shift?

> Automatic is more fuel efficient

I thought it was the opposite. Has that changed?

Yes. Technology advanced and CVTs and 10-speed dual-clutch automatic transmissions are now more (by 1-2 mpg) more efficient than manual transmissions.

I doubt it's changed under real driving conditions, with hills, valleys and overtaking happening frequently, where all types of automatic transmissions perform poorly (they can't possibly anticipate an oncoming hill or overtaking, whereas the driver manually shifts to the correct gear beforehand).

Every automatic car I’ve driven would e.g. quickly downshift when pressing down the accelerator, and while this can be laggy with older AMTs I’d assume it’s not an issue on modern gearboxes, at least the not-super-cheapo ones.

But probably more relevant, all automatics I’ve driven have “manual” shifters (paddles or +/- selector on the gear lever) which let you override the gearbox’s decisions, to an extent.

So nothing precludes anticipating your gearing, even on an automatic.

What you're talking about makes a manual have fewer torque brownouts for lack of a better term, but they'd cost efficiency not gain it. Being in a lower gear before you need it is worse for mpg than being in it slightly "too late"

I’ve been told even the old torque converter style has been upgraded with direct coupling, so you get fluid coupling (and its smoothness) while shifting, and direct coupling (and its efficiency) once in gear.

It hasn't changed, automatic gearboxes still eat up more fuel than their manual counterparts on the same cars.

I think from a purely mechanical point of view, this is the case, meaning that if you have two cars, one with manual gearbox and one with an automatic gearbox, both driving at the same speed with the same gear ratio, the one with the automatic gearbox will likely use slightly more fuel. But even this might not the case at all possible speeds. But at some speeds when the car with the manual gearbox is using the wrong gear, it might use much more gas. The problem with the manual gearbox is not in the gearbox but the human using it. First of all, not all drivers know when is the best moment to change gears and even if they know, they are not always able to change gears at the right moment. When you are turning on a crossing and accelerating, switching gears can be difficult.

Also automatic gearboxes can change gears usually much faster than humans. Operating the clutch is hard and when not done in the correct way, letting the clutch slip too much, waste energy.

Taking this all into account, in many cases, an automatic transmission might be more efficient.

I have been driving cars with manual transmissions all my life. My current car as indicator lights telling you when to change gears up and down. I often find myself skipping gears, especially when accelerating in the city, I often skip fourth gear. The car has six gears and you should already switch to the fifth gear when driving 50Km/h. My first car only had four gears, and the fourth gear was only used when driving over sixty. If a car has more gears it also means that you have to shift more often, which might make driving less efficient in city traffic due to the many more moments you shift slightly at the wrong moment.

The automatic gearbox frequently upshifts in error (for example, just before a hill, making a downshift immediate) and downshifts too late when overtaking, resulting in erratic behaviour, lots of revs, and considerably more fuel consumption.

Taking this into account, in almost all cases cases, a manual transmission might be more efficient.

None of what you describe costs fuel, nor does it cause "lots of revs"? Upshifting "too much" is the opposite, it's fewer revs (and therefore less fuel used, not more)

It’s all in how you drive. I got 50-57 mpg in my old manual. My wife had the same engine in a different car as an automatic. I would only get 20-30 in it. My car was rated for 25-30 mpg. Most people don’t know how to drive a manual transmission for efficiency or never cared to find out, so they drive it like an automatic, which the car isn’t. Thus they end up with less mpg than they would in an automatic.

Could you explain "how to drive a manual transmission" ? I have one but I've never asked myself how I could drive better...

You have control over the torque, just barely push in the gas when you accelerate and use the gears to keep up with traffic instead of the gas pedal, like on bike.

I'd just like to remind the downvoters that most early 90s compacts put down well over 40mpg with the manual, easily 50+ if you try, and around 30 no matter what you do if equipped with a 3spd auto. Depending on differences in usage patterns and driving style I low 50s vs high 20s is extreme but plausible.

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