CVT Transmissions

Sorry, not sure where to put this . . .

Does anyone know about CVT transmissions? I'm looking at a car I'd like to buy, and have a good idea of what it is, but not sure how it impacts on actually driving the car. Is it easy to drive? Is it difficult to maintain mechanically? What are the pros and cons?

Anyone mechanically savvy out there? 

Mention continuously-variable transmissions and most people (over a certain age!) here will immediately think of the old DAF cars which used it quite extensively.

Instead of the usual fixed ratios engaged by brake bands of a normal automatic transmission, the ratio can adjust to anything between its maximum and minimum.   So instead of changing from 1st to 2nd to 3rd etc. it can adjust to anything in between as well. 

The older units on DAFs did have a bad reputation with regard to reliability, but I have no idea about the newer designs.   I',ve never driven one, so can't really comment about that, but I wouldn't have thought it's that difficult to adapt to once you get used to the absence of "abrupt" gear changes.

The only thing in the states I have ever seen with a CVT are ride on lawn mowers.

My fear would be that because they are not fixed gears (and essentially you are expanding a single gear, usually a rubber belt) that long term you might have a reliability problem.  Just my opinion based on no real world experience.

Here is an article that explains them and states that they are supposedly becoming more mainstream, mostly in the response of trying to squeeze every ounce out of the petrol usage.

http://www.edmunds.com/ownership/techcenter/articles/45104/article.html

Here's another website for CVT's.  http://auto.howstuffworks.com/cvt.htm [nofollow]

I've never driven one either, but on paper, in addition to better fuel economy, it's supposed to have better acceleration and hill climbing due to the lack of "jerk" shifting between gears and better use of the engine power curve.  If possible, I'd recommend test driving a car with a CVT and a similar model without one to see if you notice any difference.

Sounds like they've developed a steel belt that's more durable than the rubber version found on previous models.  That's why CVT's are  starting to pop up in higher powered vehicles like A4's, A6's, Murano's etc. back home in the States.

Regarding repair frequency, I have no idea how they compare to mechanical or automatic transmissions.  I'm guessing the biggest issues would be replacing a belt or making sure the the two pulley halves are "shifting" together, which I'd be tempted to leave that maintenance to the professionals anyway.  And pure speculation on my part, but since CVT's aren't as common, maintenance might cost more.  Check with your dealer.