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Comment by HyperSane | Hacker News Reader

If you read the article is says that dual clutch automatics are much faster than manual transmission and most modern automatics have 7 to 10 gears for better fuel efficiency but no one is willing to use a manual transmission with that many gears.

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> dual clutch automatics are much faster than manual transmission and most modern automatics have 7 to 10 gears for better fuel efficiency

In what < $15K econobox? :)

The prior gen Ford Focus and Fiesta had a DCT, along with the C-Max.

https://en.wikipedia.org/wiki/Ford_PowerShift_transmission

It was disastrously unreliable, and they knew it, and got sued for fraud over it. So they don't use a cheap DCT anymore.

Where can I buy a < $15k econobox? Seriously, I'm looking. Yes I'm also looking at used cars, but they're also expensive.

Chevy Spark: https://www.chevrolet.com/cars/spark

Nissan Versa at $15.5k: https://www.nissanusa.com/vehicles/cars/versa-sedan.html

Kia Rio and Hyundai Accent aren't too far off at $16.5k: https://www.kia.com/us/en/rio

https://www.hyundaiusa.com/us/en/vehicles/accent

Mitsubishi Mirage, too: https://www.mitsubishicars.com/cars-and-suvs/mirage

I believe every US market Nissan sedan, including the stanza at the lowest end, come standard with a continuously variable transmission programmed to fake the sensation of shifting at fixed gear intervals. so in that case, you get an infinity of 'gears'

The Mitsubishi Mirage (Space Star in parts of Europe) is offered with both manual and CVT transmission options.

According to the figures in the manual for the 2016 model revision (https://mitsubishi-motors.co.uk/wp-content/uploads/2021/06/1...), the CVT is indeed supposed to be slightly more efficient, according to the figures for the 2019 model (https://mitsubishi-motors.co.uk/wp-content/uploads/2021/06/1...) on the other hand the CVT is consistently slightly worse than the manual transmission.

(Also somewhat interestingly, in some cases the auto engine start-stop system actually seems to increase nameplate consumption/CO2 emissions.)

I'd take the manufacturer's efficiency claims with a grain of salt; they are not going to be individually reproducible, let alone comparable to each other for those models. You can drive a manual for fuel efficiency, and be assiduous in doing so; there is intent and skill involved.

Apart from Dominic Toretto and his merry band of car enthusiasts, for whom 7-10 are definitely low numbers ;)

Truckers have entered the thread.

(I agree though, since I don’t drive a semi or dump truck.)

Trucks don't have 18 gears for efficiency. They have 18 gears because low-revving diesel engines have small power bands; mix that with heavy loads, and it pretty much necessitates having a lot of short, closely-spaced gear ratios, so that maximum torque can be achieved consistently, no matter what speed you're at.

Also, FWIW, they don't just pick between 18 gears with a single shifter. They have multiple inputs that allow shifting between multiple combinations of gears, some requiring clutch to change and some not, as they gain speed. Most trucks still only have 6-ish positions for the main gear shifter to slot in to.

Sounds like they could really use a CVT. ;)

I'm sure they would love one, but it's probably not that easy/cheap to find one that can handle that much torque with such heavy loads. The biggest/heaviest trucks just end up using electric/traction motors running from diesel generators, so they don't need a transmission at all.

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