Hi all,
I am considering getting a Ford Fiesta, the 1.4lt which has a semi-automatic gearbox. I will mainly be doing driving throughout and around London hence the reason to go for an automatic.
Has anybody ever owned this car or have one currently? I have no experience of the semi-automatic gearbox, so looking for peoples opinions on this if they have owned one in the past.
Thanks!
9 Comments
sorted byI haven't tried that gearbox, but generally speaking automated manuals aren't known for their smoothness so if that's your reason for buying then it may not be the ideal choice unless you plan to change gear manually and just want the clutch pedal removed.
I am not 100% how the semi automatic gearbox actually works. So you still change gears like a manual however there is no clutch?
I did some research however I can't seem to find any information about this gear box, nothing on youtube either explaining how this works..
The term semi-automatic seems to get applied inconsistently so don't assume they're all the same.
An automated manual gearbox like the Durashift on the fiesta is a standard manual gearbox with computer controlled motors and soldenoids outside it to change the gear for you. Some automated manuals offer controls to allow the driver to tell the computer to change gear and some don't. As these controls are just buttons sending an electronic signal they can be in any form - paddles behind the wheel and pushing the gearlever up and down being the most common.
Looking around there's a good description of how the Fiesta's box and controls work in this review:
buyacar.co.uk/car…tml
Thanks for the link. After reading it, it appears to have some extra trickery then a normal automatic box but does practically the same thing. You can put it in ASM mode or SSM mode. ASM is a automatic mode where as SSM is the mode where you can manually go up and down gears as you choose.
What do you think are the differences between this Durashift gearbox and a standard Automatic gear box? The main thing I am looking for is an automatic gearbox so its easier driving around in the city.
Earlier semi-auto's were prone to poor shifting, bad timing of shifts (with a momentary loss of power), and to wear and poor lifetime of the auto clutch.
A big advantage of the semi-auto compared to the normal (torque converter) auto, is it's as efficient as a manual ... The torque converter on a traditional auto has losses - some systems alleviate the losses by activating a converter lock when at steady speed.
Not sure how semi-auto performs "creep mode", other than by slipping the clutch.
NB. Even on a traditional auto, you should not abuse it by using any more than idle while stationary for any time. To prevent rolling back on a hill, the handbrake should be applied as holding using engine power is unsteady, unsafe and may overheat the transmission fluid.
Automated Manuals are arguably the normal type of automatic for small, cheap cars.
For larger cars the torque converter automatic is most common. Instead of being a computer controlled manual it's an entirely different design that works mechanically. It doesn't use it's power very efficiently though, so it requires more horsepower which means the engine burns more fuel.
Other common types of automatic would be:
Dual Clutch Automatic. A refinement of the automated manual that has a second clutch to pre-select a gear which results in a lot lower incidence of jerky shifts.
CVT. A continuously variable transmission without individual gears. Popular on Japanese cars, the primarily complaint against the CVT is that it's behaviour in keeping the engine at high revs when accelerating hard can produce a lot of noise.
Both dual clutch and CVT automatics are more efficient than torque converters.
Implementations do vary though, so you probably want to test drive a few to get an idea of which you dislike so you can discount any that don't have a particularly good implementation of that technology.