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Hi Guys, I just wanted to introduce myself and to ask a question. I've been a Volt owner for about two months now and I'd like to learn a little more about its transmission. I know that the Volt doesn't have a conventional gear box, but that's about all I know about it. Can some explain to me in laymen's terms how it differs from a standard transmission?

By the way, I LOVE this car!

Steve
 

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Welcome to the group. If you do a search on YouTube for 'Chevy Volt Deep Drive' you will see a multipart series on the transmission and how it works. There are other ones also.
 

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Yep, I second the YouTube "Volt Deep Dive." Very impressive. I've pointed a lot of people who have any technical interest in cars toward those links. Great explanation and visuals, straight from the horse's mouth.
 

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Welcome and enjoy learning more about the volt. The videos on the deep dive are great.
If you are more of an exploratory or kinetic learner you might enjoy
http://eahart.com/prius/psd/

which is an interactive simulator of the continuous variable transmission based on sun+planetary as configured in a Prius PSD. This is similar to a volt, but the main traction motor is in the middle. The video shows some of the same concept but you don't get to interact with them in the video to build your intuition. (Someone should do a nice interactive volt.. the source for the PSD done is on the above site).


You might also find this thread useful (I did)
http://gm-volt.com/2011/12/09/solving-the-volt’s-extended-range-combined-mode-power-split/
 

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There are lots of detailed summaries out there, and some links have already been provided. Basically, at lower speeds or higher loads, it operates as a direct drive transmission for the main drive motor (called Motor B in diagnostics/service manuals,) at a 7:1 overall gear ratio (similar to 2nd gear in many cars.)

At higher speeds, the ring gear unlocks, allowing the car to operate in a prius-like CVT mode. With the engine on in CS mode, it frequently chooses to run this CVT like a fixed gear - by pretty much stopping the sun gear with the main motor, it allows the engine to drive the wheels directly at around 3.1:1 - similar to many cars in 6th gear. (Of course, the Volt also keeps the engine wide open virtually all the time for efficiency reasons.)
 

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The first time I found out about planetary gear boxes and CVTs was from a guy named John. His website can be found googling john1701a. That might be his dot com domain. Amazing graphics and explanations of it. He did all this way back when video media wasn't as popular on the web so it's very simple, many of them are gifs with explanations.

He was somewhat of a founding member in the world of hybrid driving.
 

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The first time I found out about planetary gear boxes and CVTs was from a guy named John. His website can be found googling john1701a. That might be his dot com domain. Amazing graphics and explanations of it. He did all this way back when video media wasn't as popular on the web so it's very simple, many of them are gifs with explanations.

He was somewhat of a founding member in the world of hybrid driving.
The PSD demo is not john's cite (though he is acknowledge, with a link to his site).
He does have a good word-document to explain it.
 
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