My '04 Prius is the third CVT transmissioned vehicle that I have owned and is by far the smoothest running. Aside from all of the other virtues of the Prius, IMHO this undermentioned/underappreciated feature of the Prius definitely deserves high praise. Before the Prius, I owned a 2000 Honda Civic HX coupe with CVT followed by a 2003 Saturn Vue 4 cylinder, all-wheel drive and CVT transmission. While driving the Vue, it sounded as if you were riding inside a Singer sewing machine. GM must be having issues with this CVT as even though there haven't been any recalls on it that I'm aware of, late this winter GM sent out a notice to current owners extending the warranty on the CVT from three to now five years! Fortunately, aside from the annoying sound it produced, I had no mechanical problems with the Vue CVT itself. I would probably still have Honda Civic HX today rather than having sold it to get the Vue had we not needed a more practical, somewhat economical SUV (contradiction in terms, I know...) that we could place a rear facing convertible child safety seat into and not have to be a contortionist in order to be able to get the baby in and out of car. The CVT in the Civic HX was quite economical and easy to drive. 34-38 EPA was realistic. The Vue's mileage sucked at frequently less than 22-26 EPA. I wonder what the engine/transmission configuration is going to be on the Saturn Vue hybrid when it comes out in '05 and if they intend to stick with the CVT. Has anyone else out there had CVT experiences prior to getting their Prius and what is your opinion of the Prius CVT?
Please not that the Prius DIES NOT have a cone-and-belt type transmission. See the general theread "planetary" or something like that for the details. Brian
> GM must be having issues with this CVT as even though there haven't been any recalls on it that I'm aware of Back in January, GM halted production entirely. Something was seriously wrong with their CONE & BELT design. I haven't heard that production has resumed. Honda has also had problems with their CONE & BELT design, but they seemed to have fixed it rather quickly. Ford has a CONE & BELT design coming out in the new "FreeStyle" vehicle (a wagon that looks like a SUV) this fall. That should be interesting. Toyota's CVT is entirely different. It is of the PLANETARY design. So none of the issues with other automakers apply to Prius.
As I've posted before, I FREAKING LOVE the CVT!!! I didn't even know what this was when I was looking at the Prius, and now that I have one (as of last week) it's a VERY pleasant surprise. Smoothest riding car I've ever had.
CVT is definitely one of the many reasons I love this car. My favorite thing to do after people that don't know who ride with me is ask them if I shifted okay (after the drive, of course) and they always say that they don't really remember and it must have been okay. ...that is until they get in the car again and notice that it doesn't ever shift.
Yup, my first CVT was the Saturn VUE. I also test drove the Subaru Justy, and Honda Civic HX. My VUE was a lemon, and is why I now own a Prius. GM had a few belt failures, and this is why they halted production on the CVT. Last I heard, production was resumed, and the extended warranty issued for current owners. As for my VUE, GM installed a new tranny in it at 6700 miles as it was sucking air on turns. I also had to live with a shuddering torque convertor between 55 and 65 mph for about 9 months while they figured out the cause, and required software patch to fix it. Then of course, is my snowmobile. It has a mechanically actuated CVT as well. Snowmobiles use a rubber belt though, and they are not a lubed tranny. The pulleys are opened and closed by weights and springs. Beautifully simple design. I have a hard time calling the Prius transmission a CVT. I still haven't quite figured out how they made a planetary gearset, which would normally have three stepped ratios, work like they did.
I agree that this is one of the better and less recognized features of the car. I like the CVT also. Driving up a steep hill (7 % grade) teh Prius moves relatively smoothly, when an automatic does too much shifting, trying to adjust to the hill.
Hi folks, One word adequately describes the Prius experience, SMOOTH! From what I can understand, the car doesn't have a CVT in the normal sense. The planetary gear unit is basically a torque sharing/combining or "Power Split" device. For those that are mechanically minded, check out http://auto.howstuffworks.com/hybrid-car9.htm Also, Graham's site has an excellent explanation of how it all works. http://home.earthlink.net/~graham1/MyToyot...PriusFrames.htm Regards, kenmac
Thanks for all of the comments! Now, are there any diehard manual shifter types out there that wish that a 5 or 6 speed was available?
This car is not possible with a manual gearbox. It would need to be configured in a mild-hybrid (i.e. Honda Civic Hybrid (a.k.a. HCH)) setup before you could row your own gears. Because of the nature of the power split device, we can operate using either power source independantly or in combination. The HCH is gas or gas with electric assist. I suspect the Prius would actually get worse MPG as well with a manual gearbox.
I was (note the past tense!) a die-hard manual-transmission kind of guy. I like to be in control in all aspects of my life. With a manual, I decide when to shift. Maybe I want more torque for quicker acceleration, I shift later. Maybe I want more economy, I shift sooner. Maybe I want a jackrabbit start, I rev the engine before letting out the clutch. Etc. But how are you going to control manually the interconnection among a gas engine, two (count 'em! two) motor-generators, and the wheels? A transmission won't do it. Elephants can't climb trees, anteaters can't fly, politicians can't tell the truth, and a transmission can't connect an ICE, two MGs, and the wheels. The prius was impossible until Toyota invented the HSD, using the planetary power-split device under strong computer control. The world has changed. Transmissions are obsolete. Now we have to change the way we think about how power gets from the power source(s) to the wheels.
Hi again, Another site with Prius info - .pdf doco. - http://www.worldenergy.org/wec-geis/global.../NZConf/10c.pdf kenmac
Interesting to compare this information (which is for a Prius Classic) with what I've seen of an '04 Prius. Doesn't look like there's much difference in the basic design. Is there any significant, major difference between the Classic and '04 Prius Hybrid Synergy Drive? The only one I could think of was the larger batttery.
Different design of MG1 and MG2 to get higher sustained RPM and a smaller battery and a different design for the HV electrics whereby the main generator produces a higher voltage (up to 500 volts) compared to the Classic's lower RPM and 273 volts. 2K4 battery is 200volts compared to the Classic's 273 volts. There are other differences as well but this is a simple guide to the electrics.
There's a website listed in a different thread (at toyota.co.jp) which overviews more specific differences. Some include motor design (including magnet placement, etc.), ICE changes, etc.
