The CVT (continuously variable transmission) is becoming more popular as a replacement for the standard torque-converter transmission, but there are a few things that you should know before you run down to your local dealer and buy a vehicle with a CVT. These facts will ease your adjustment to this type of transmission.
What Makes Driving a CVT Different?
First you must realize that a car sporting a CVT feels somewhat unnatural and can even be annoying when first driven. In fact, you will probably notice one of these occurrences as soon as you step on the accelerator and feel the engine immediately crank up, with the accompanying RMPs, from the low end to high very quickly. This quick acceleration, especially in a car equipped with a small engine like a four-cylinder, can result in an unwelcome increase in noise volume.
How Does a CVT Work?
That being said, you may wonder how the CVT works. Well, first let us note that, in a traditional transmission, you have various gears that provide different ratios depending on your driving condition. This is similar to what you see in a 10-speed bike where the chain moves over different gears to control its speed. In the case of the traditional automatic transmission, the transmission selects which gear to use (except in override settings where the driver selects the gear). These settings are normally set to use low gears for starting, middle gears for acceleration and passing, and higher gears for highway cruising.
This is where the CVT differs in that there are no gears. Instead, a CVT uses variable diameter pulleys, with one pulley connected to the engine and a second pulley attached to the drive wheels. These pulleys are most commonly connected using a metal belt that dictates the ratio (which is limitless) as the pulleys come closer together or pull apart. Of course, this is a simplified explanation, but if you wish to get into the true mechanics of a CVT, I would recommend that you do a Google search to locate many of the fine articles that better describe the CVT.
What Has Been My Driving Experience?
My own experience with this type of transmission began when I purchased a new 2009 Nissan Rogue AWD right off the showroom floor. I had no idea what a CVT was and actually had no idea the car came equipped with one. Admittedly, the salesman attempted to explain it to me, but until you drive one, you don’t quite understand the concept. What I did glean from the rhetoric was that my driving experience would be different; in the beginning, I figured that it would just be something to which I needed to adjust. However, adjusting to driving the SUV was, shall I say, challenging in that I am somewhat sensitive to loud noises. Due to this, I found the engine noise generated by the quick acceleration somewhat disconcerting. This, in addition to the surge in power as the engine instantly ramps up to full RPM power, leaves you with a feeling that the transmission is trying to catch up. However, after driving the vehicle for about six months, you accept the noise upon accelerating from a stop as normal and drive the vehicle accordingly.
So, while it seems like I am being negative about CVT, this isn’t the case. I find that where the CVT shines is accelerating up steep grades and hills. I especially noted this on a trip through Arkansas as we headed to Texas to visit our oldest daughter and her family. Our route takes us through the Ozarks, which requires traveling roads that maneuver through some very hilly countryside. We have since had occasion to repeat the trip many times and I am always amazed at how easily the Rogue handles the terrain and accelerates through the hilly twists and turns. The smooth driving doesn’t stop there, however, but extends to highway traveling. On highways, where the speed is posted as 70 MPH, there is absolutely no engine noise since the engine RPMs are usually at or near 2k.
Does the CVT Increase Gas Mileage?
While the Rogue has been a reliable and satisfactory vehicle, you may wonder how it does with fuel economy. The EPA estimates mileage for the Rogue AWD MODEL as 21 MPG city and 26 MPG highway. For the most part, I can confirm that the EPS estimate is accurate. Given that, I believe the gas mileage is okay, but nothing to write home about. Is this good gas mileage? I can’t answer that since Nissan doesn’t make the Rogue with anything but a CVT, giving me nothing for comparison.
What Other New Models Will Come Equipped with the CVT Besides Nissan?
So, while Nissan was the first manufacturer I encountered that retailed vehicles with the CVT, these transmissions are gaining in popularity and are now available in hybrid models from Toyota and Lexus. In addition, the Toyota Prius also uses a CVT to propel it along the roadway and it is rumored that when Honda introduces its new Accord this fall, it may also come equipped with a CVT.
Over all, my personal experiences have been positive, but before you consider buying a vehicle equipped with a CVT, you should be aware that other consumers have noted some reliability issues. These issues came to my attention approximately six months after I bought my Rogue. It was at this time that Nissan extended the warranty on the CVT from three years/36,000 miles to 10 years/120,000 miles. This extension, according to different Nissan forums, was the result of Nissan attempting to avoid a class action lawsuit by consumers who alleged issues surrounding the CVT. I have no solid information backing this as the reason that Nissan extended the warranty, but according to a letter I received from Nissan, the extension was made to address consumer concerns about the reliability of the CVT. No more, no less.
Source: Green Car Reports
CC licensed Flickr photo above shared by Bolt of Blue