I know the details of the 2.4 4-cyl DOHC 16V engine being a joint venture. The engine should be solid. Does anybody know the origin of the CVT II design?
http://www.autofieldguide.com/articles/wip/0606wip05.html
Chrysler’s powertrain engineers began devising the technology to accommodate a low-range mode on the existing Jatco CVT in 2003, when the Patriot began crystallizing through the development process. “We knew right from the start that we wanted the Patriot to be Trail-Rated, so we tasked ourselves with developing a low-range CVT in-house,” says Matt Loddane, chief engineer for the Patriot and its platform-mate Jeep Compass. “The key was to get all the capabilities without a two-speed transfer case.” Chrysler engineers patented the CVT low-range system, dubbed CVT2L.
When the low-range mode is selected via a switch, a controller determines whether the vehicle is traveling at an acceptable rate of speed (the system can only be activated at speeds below 25 mph) and then engages a coupling mechanism, via specially developed software programming, to engage the secondary drive wheel while the CVT moves into a higher final drive ratio of up to 19:1, which is more than enough to traverse just about any dusty trail or rough terrain. Loddane dismisses any concerns over potential durability issues of operating a CVT at such output levels, adding that most of the attention during development was focused on perfecting the calibration and feel of the system. “We had to do a lot of work to make sure the low-range mode would operate like a traditional system from a customer standpoint, so that it would sound and feel familiar,” he says.
Other Info:
Why a CVT? Basically, continuously variable transmissions have fewer moving parts, which cuts costs and should also prove more reliable, plus the gearbox type's low resistance makes for better acceleration and enhanced fuel efficiency - a best in all world's scenario. Dodge was smart to go with the well proven Japanese supplier instead of trying to build their own in-house CVT, as the transmission's reliability will make for a happier Caliber customer in the long run.
Fluid & Chain Info:
I read somewhere that the CVT used to be a rubber belt, but now it is a metal that is extremely strong. But I think the transmission fluid actually has rubber particles in it now which helps the metal belt to grab and have traction. Slipping of the belt is bad so I also read somewhere that the computer will limit how much torque is applied at any one time to improve the reliability of the belt and avoid slipping. This is the reason some people say the Caliber will be a little sluggish going 0 to 15.........the computer has some kind of limit in this range so people don't gun it and apply too much torque for the CVT to handle.
