What are the advantages of a CVT? What are the disadvantages? How does CVT affect fuel economy?
The advantages include better fuel economy and an absence of noticeable shifts. The disadvantage (at least with Nissans) is a durability problem.
In theory a CVT should provide the best possible economy, because it can always deliver the best possible gear ratio for conditions. Some cars that come with CVTs are delivering better real-world mileage than their non-CVT counterparts.
As always, there are many things that contribute to fuel economy. The transmission type is just one variable in the equation.
Engines have areas within their power curves where they operate most efficiently for any given load conditions. A constantly variable transmission allows the gear ratios to adjust such that the engine will always be operating in its optimum no matter what the speed of the car. It’s like having an infinite number of gear ratios constantly shifting.
I don’t know the downsides. People have been trying to design CVT trannys for as long as I can remember. Only as of recently with hybrids has this stuff come to pass.
I believe CVT uses a lots of belt compare to the regular tranny. Just like cars with timing belt compare to timing chain. The belt (rubber) needs to be change at some interval & then that’s when you will feel the financial impact.
My 98 Honda Civic HX with a CVT has 230,000 miles and I could not be happier. It shifts smoother then any other automatic transmission and the car gets 350+ miles on 12 gallons of gas. It drives well around town, but if you push the car, braking hard into a corner and then get back hard on the gas, the transmission returns to a sedate 3000ish RPM running zone. The CVT is NOT for race cars. Thus, if you want to drive a race car, get a manual transmission. If you want good milage and a reliable, sweet shifting automatic get a CVT.
The only downside to the CVT has been durability and repairability. They work best in low power, light weight vehicles. The concept was pioneered in snowmobiles…
Does anyone have efficiency figures, in terms of power losses for CVT vs. manual vs. automatic?
You will get great power with a CVT transmission. You will never lug the engine. An 03 Saturn Vue (fake SUV) would sometimes get 29 MPG highway with the vehicle empty. The highway run was from Santa Barbara to San Diego. If you are tired of downshifting on uphill runs, CVT is da bomb. Mine seemed to pick up a lot of speed going downhill because the trans just lets you go and go.
I’ve had the pleasure of taking an 07’ Maxima for a fairly lengthy drive.
Let me say this… dayum… she’s FAST.
Acceleration and power delivery are incredibly smooth. Instead of feeling like I was accelerating down a highway in a fast car, I felt like I was being propelled down a runway in a plane. Both the acceleration and the smoothness were so identical that if I closed my eyes I’d have been able to fool myself.
Any lightly powered car will always be just that, lightly powered. Even a CVT can’t change that. But if you buy a powerful car, a CVT can make great use of all that power. And in the case of the Maxmima, make it a GREAT ride.
Since the car’s not mine I can’t say about fuel economy and since it’s new no one can say about durability.
I don’t know about durability…but I do know they’re NOT made towing or moving something very large. The other MAJOR disadvantage…is that if there is a problem with CVT…it CAN’T be serviced…You replace it (about $7k). Now if it’s durable…this probably won’t be an issue.