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Sequential shift transmissions

While looking for a new auto I came across something called an automatic sequential shift transmission. I know basically that you can use them as an automatic or choose the gear you want. If someone wants to expand on this great.
What I need to know is are they any good, are they dependable, are they outrageously expensive to repair etc. Do they all use the paddles? This particular tranny is in a Ford Fiesta 2011
While we’re at it can some one fill me in on CVT’s as well???
Many thanks!

Automatic Sequential Shift Transmissions (As Opposed To Automatic Random Shift Transmissions ?)

What next ? Dehydrated Water ?

Mr. Obvious, here. Most automatics that shift randomly are in the repair shop.

CSA

They are similar to motorcycle transmissions – they can go up or down one gear at a time. BMW, Porsche, Ferrari, etc. have been migrating them from race cars to consumer cars. Many shift in 50 msec or less, perfectly rev matching down shifts. Done right, they are a lot of fun to drive.

Constantly Velocity Transmissions (CVTs) don’t have “gears” per se, but infinitely step less ratios. They try to keep the engine reving in its sweet spot to maximize efficiency. Drive a few different ones and pick what’s right for you.

Reliability and cost of repair is as much of a function of how you drive, how you service your car as the design of the transmission.

I believe this is a dual-clutch transmission. You can read more at en.wikipedia.org/wiki/Dual-clutch_transmission. As twotone says, these shift much more quickly than a normal automatic transmission, so they’re good when performance is a concern.

Lion9car, is correct. It’s more like an automated manual than a traditional slushbox. There’s no torque converter either. The theory is that you don’t have the inefficiency inherent with traditional automatics (pumps, slippage, etc.) . They used to be only available on high end sports cars, but are now trickling down to more mundane vehicles. They haven’t been perfected yet and supposedly they tend to operate less smoothly at low speeds/low RPMs.

Maybe, but I don’t think this is what’s in a Ford Focus or the other mainstream cars that have manual shifting options. In my Acura, Pontiac, etc. its just a standard automatic with the ability to move the shift lever into manual mode is all. When its in manual mode, you just push the paddle or bump the gear shift and it shifts. Nothing special. CVT on the other hand is like a snowmobile transmission, and I may be wrong, but have had some issues and are expensive to repair.

@Bing
It’s not standard traditional automatic

I own a 2012 Focus with the dual clutch automated transmission, and after the firm ware update the transmission works good. I am averaging 32MPG. Things I like about the transmission are.

Excellent fuel mileage.

Internally it is a simple manual transmission that does not use ATF fluid.

Clutches are external of the transmission just like a manual transmission and similar to replace.

OK, I stand corrected. That’s a different animal than GM or Honda.