JeepForum.com

JeepForum.com (http://www.jeepforum.com/forum/)
-   Compass & Patriot Forum (http://www.jeepforum.com/forum/f98/)
-   -   Like wine i think CVT hates me (http://www.jeepforum.com/forum/f98/like-wine-i-think-cvt-hates-me-1498994/)

Thunderai 03-25-2013 05:25 PM

Like wine i think CVT hates me
 
I have a new 2013 jeep compass 2.4l latitude 4x4 with a cvt transmission. I think the transmission hates me. Like many people onlinewho find the cvt differnt to drive i find it odd and perhaps its me, but i think my cvt dislikes to shift when i think it should.

It happily stays at a higher rpm then it should and dislikes to shift up to lower the rpm. If i control the shifting i can increase the fuel economy but the fuel economy cvt happily burns 17mpg city wasting rpm.

Is it my jeep cvt being normal or should i be worried?

FujativeOCR 03-25-2013 05:53 PM

Quote:

Originally Posted by Thunderai
I have a new 2013 jeep compass 2.4l latitude 4x4 with a cvt transmission. I think the transmission hates me. Like many people onlinewho find the cvt differnt to drive i find it odd and perhaps its me, but i think my cvt dislikes to shift when i think it should.

It happily stays at a higher rpm then it should and dislikes to shift up to lower the rpm. If i control the shifting i can increase the fuel economy but the fuel economy cvt happily burns 17mpg city wasting rpm.

Is it my jeep cvt being normal or should i be worried?

The 17 mpg city sounds normal to me. The shifting doesn't, since they don't really shift per say. Mine only drops rpm once, and it varies depending how hard it's being stepped on.

Thunderai 03-25-2013 07:52 PM

When i drive you hear the engine rev really high and it stays there for awhile. If i manually shift up i can decrease the rpm, but why do i have to shift it up? It seems to shift really slow. Its totaly possible the cvt is so different.

FujativeOCR 03-25-2013 09:08 PM

Quote:

Originally Posted by Thunderai
When i drive you hear the engine rev really high and it stays there for awhile. If i manually shift up i can decrease the rpm, but why do i have to shift it up? It seems to shift really slow. Its totaly possible the cvt is so different.

It doesn't shift.

aroundincircles 03-26-2013 03:37 AM

There are no gears to shift, and it takes a different driving style. That is why most people don't like the CVT, as you have to almost relearn how to drive a car. Can you provide more details? 2.0. Or 2.4? Fwd, FDI, fdii?

Wmillonig 03-26-2013 06:07 AM

So, here's an example of the auto stick with a CVT, if you're coming down a hill and want to use a little bit of engine braking to keep your speed rather than brakes, each time you "bump" the stick to the left, you drop a "gear". If you drop to 4 or 5, and want to go back, you have to push and hold momentarily the stick to the right and it'll go back to "D" and behave normally, otherwise it'll stay in the last number selected and the RPM will go up when you accelerate. If you drop a couple of gears and then subsequently come to a complete stop, it'll start in "1" and stay there till you either shift it manually, or bump and hold to get back to "D". This happens to me all the time.

yougotdslapd 03-27-2013 04:14 AM

That sounds a little abnormal to me. My CVT gets me 21 mpg city. Before this I was driving a 6 cylinder Ford explorer. I didn't really change my driving habits. You shouldn't feel the CVT shift gears, but you can watch the tachometer and see the RPM drop when it does. You don't see a drop in RPM? In other words, you stay in gear 1 when its in automatic, or what?

Wmillonig 03-28-2013 04:40 AM

not sure if you're asking me or the OP? But no, you don't feel the CVT shift, however if I use the auto shift to lower the number then it starts and stays in "1". At least til I bump and hold it back to D. I've never run it to the redline to see if it does anything else. Engine braking isn't nearly as effective as a conventional tranny, but in the hilly neighborhoods around my home, it keeps me at a proper speed.

WingedScapula 03-31-2013 06:03 PM

Quote:

Originally Posted by Wmillonig (Post 15206826)
not sure if you're asking me or the OP? But no, you don't feel the CVT shift, however if I use the auto shift to lower the number then it starts and stays in "1".

You've given some excellent advice. I'll just add a few more observations: there is a single "shift" that occurs somewhere in the 10-20 MPH range, depending on how hard you're accelerating (if you're accelerating slowly then it's around 10 MPH). I was under the impression that this is like a true first-gear that hands off to the CVT, but I don't know for certain. There are also some weird things with the electronic shifting. For example, when taking declining hills, sometimes manually placing the vehicle into 6th gear slows the vehicle down, while other times I've found that it causes the vehicle to pick up speed. It probably has to do with the initial speed and the angle of decline, but I haven't done this enough to know exactly what it is yet. It seems counter-intuitive that manually setting into the highest "gear" should cause engine braking, though!

Thunderai, I don't know if this explains your observations, but I've also noticed that sometimes the transmission is a bit touchy and seems to maintain higher RPMs inappropriately. I usually notice this when the engine is cold and is still warming up. I find that if I let up on the accelerator a bit then the RPMs drop down to their normal low range (~2000 for my vehicle, freedom drive 1), and then depressing the accelerator to where I was before doesn't cause the RPMs to raise up much. For some numerical examples, the RPMs might be around 2500 to 2700 RPM, slightly letting up on the accelerator drops it down to 2000, and then returning to where I was before brings it to 2100 RPM. It doesn't happen to me all that often, though.

Dacaur 04-01-2013 08:00 PM

Quote:

Originally Posted by WingedScapula (Post 15225019)
You've given some excellent advice. I'll just add a few more observations: there is a single "shift" that occurs somewhere in the 10-20 MPH range, depending on how hard you're accelerating (if you're accelerating slowly then it's around 10 MPH). I was under the impression that this is like a true first-gear that hands off to the CVT, but I don't know for certain.

Just FYI, the CVT doesnt ever shift. what you percive as a "shift" is actualy just something programed into the trannys programing to make people think its shifting.... Same thing with the autostick, all you are doing is forcing the tranny into a lower or higher "gear", but its not really a gear, its just a different ratio. CVT's dont have gears like a normal auto tranny, inside your CVT you will find, basicaly, two pullys connected by a metal belt. the "gear" ratio is controlled by, basicaly, varying the size of the pullys....

So why the fake shift?
When the first generation of CVT's came out, people wouldnt accept them, they kept bringing them in thinking something was wrong, becuase it was "stuck in gear".... Of course being used to a normal automatic, when you are accelerating and the engine revs high and stays there, it IS stuck in gear, right? But of course, thats normal operating procedure for a CVT....... So by programing in a fake shift at about the point where a "normal" auto does its first to second shift, they have tricked people into accepting it, and saved a whole lot of uneeded "service" calls......

You will notice is you accelerate full throttle, you dont get that "shift", because in reality, it slows things down, so when you are asking the tranny to give you all its got, it forgoes the fake shift and just revs up and goes....

Gramps 04-02-2013 04:07 AM

Correct, the 'gears don't shift, the are programmed and will vary anywhere between 2.349 - 0.394 depending on the Variator position.Transaxle Ratio - 6.12, This calculates out to 14.37 in low and 2.41 in high.

I have not found out what the electronic settings are for the other four positions of the variator.

Thunderai 04-03-2013 09:13 AM

The compass has a Jatco CVT Transmission and I am getting more used to it, but at the same time I wanted to know more about what I'm feeling and seeing so I mapped the transmission 'gears'. Now before everyone screams there are no gears...I know, but their are ratios I can sort of control with the autostick. The interesting part about this chart is that it points to something I already knew, the vehicle likes 30mph at fifth gear. There is good fuel economy there and although sixth gear has better economy at 40mph, 40mph on a city street is uncommon.

http://i18.photobucket.com/albums/b1...psa47a710b.png

FujativeOCR 04-03-2013 10:50 AM

Depends on your city. Most streets in Fresno where I live, speed limit is 40-45.

Gramps 04-04-2013 06:17 AM

Nice chart and thanks for doing it. Like FujativeOCR hinted at this can change according to the demand put on the engine with hills and such, i.e. the demand that you put on the engine.

Thunderai 04-04-2013 04:34 PM

For the most part each element was tested in the same route so that should minimize some of the variation. Different routes for different speeds but more or less as close as possible.


The time now is 11:14 PM.

Powered by vBulletin Version 3.8.4
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.