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  #25  
Old 07-17-2012, 10:22 AM
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Re: Ready for some tuning? Look here!

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Originally Posted by JTS97Z28 View Post
Yes I would say that's a good description of how it feels my jeep drives. For example there is this intersection that I go through everyday going to work. It's a right turn with a slight incline that starts as you are turning. Every day my jeep does the same thing where it will shift into 2nd or 3rd (can't remember which) and will literally big itself at like 1100rpm while I'm trying to accelerate up an incline with cars behind me. Then I either gotta push the pedal down to atleast 50%+ to get it to kick down or I use the autostick to do it myself. And then there are days when I drive my wife's Honda and it shifts at perfect times everytime. Just annoyances like that I wish I could fix.
Same problem with mine. I don't know if it's all chrysler vehicles or just this one, but the shift points are terribly laid out. The v8 trans programming is setup to eliminate any chance of using the available power of the vehicle. When I am going 45-50mph and start moving up an incline, if I push down on the gas a bit, it will just sit in gear churning away not accelerating. If I push it further, it sometimes drops down a gear, but it seems to never be in the correct gear when you want to accelerate.

The worst is in the 35-45mph speed zone. Lets say you need to get around someone or just pick up some speed to get through a light. You don't need the car to kick to the lowest gear it can and jump to 4500rpm+, but you want it to get out of the 2k range. If I give it 50% on the gas pedal it will hesitate and then when you give it more because you wonder where the shift is, it says "oh, you want me to actually accelerate" and it drops to the lowest gear finally moving.

Sorry for the rant, but this is the one thing that I hate about this vehicle. Can't wait for the 2014!
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  #26  
Old 07-17-2012, 03:00 PM
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Re: Ready for some tuning? Look here!

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Originally Posted by amill View Post
Same problem with mine. I don't know if it's all chrysler vehicles or just this one, but the shift points are terribly laid out. The v8 trans programming is setup to eliminate any chance of using the available power of the vehicle. When I am going 45-50mph and start moving up an incline, if I push down on the gas a bit, it will just sit in gear churning away not accelerating. If I push it further, it sometimes drops down a gear, but it seems to never be in the correct gear when you want to accelerate.

The worst is in the 35-45mph speed zone. Lets say you need to get around someone or just pick up some speed to get through a light. You don't need the car to kick to the lowest gear it can and jump to 4500rpm+, but you want it to get out of the 2k range. If I give it 50% on the gas pedal it will hesitate and then when you give it more because you wonder where the shift is, it says "oh, you want me to actually accelerate" and it drops to the lowest gear finally moving.

Sorry for the rant, but this is the one thing that I hate about this vehicle. Can't wait for the 2014!
Nice explanation. I experience the same thing.
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  #27  
Old 07-18-2012, 03:01 PM
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Re: Ready for some tuning? Look here!

Just manually downshift... the slap stick is there for a reason.
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  #28  
Old 07-18-2012, 03:23 PM
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Re: Ready for some tuning? Look here!

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Originally Posted by Jeff_Jeske View Post
Just manually downshift... the slap stick is there for a reason.
I dont want to manually downshift, I want the car to do it on its own like most cars out there.
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  #29  
Old 07-18-2012, 04:45 PM
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Re: Ready for some tuning? Look here!

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Originally Posted by JTS97Z28 View Post
I dont want to manually downshift, I want the car to do it on its own like most cars out there.
There hasn't been an auto transmission since the 727 days that shifted on its own properly all be itself. Most cars out there have one issue or another. None of them can anticipate what you want. Perhaps in 2020 there may be a unit that can read our mind and anticipate.

Sometimes you just have to get off your butt and put some effort into driving.

BTW, have you tried driving a combination of sport and tow/haul mode (if you have them)? I suspect you don't like it because you want better mpg....


When the 8 speeds come out, they will have 8 possible wrong gears, a little worse than the 5 possible wrong gears today...
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  #30  
Old 07-19-2012, 08:59 AM
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Re: Ready for some tuning? Look here!

Quote:
Originally Posted by amill View Post
Same problem with mine. I don't know if it's all chrysler vehicles or just this one, but the shift points are terribly laid out. The v8 trans programming is setup to eliminate any chance of using the available power of the vehicle. When I am going 45-50mph and start moving up an incline, if I push down on the gas a bit, it will just sit in gear churning away not accelerating. If I push it further, it sometimes drops down a gear, but it seems to never be in the correct gear when you want to accelerate.

The worst is in the 35-45mph speed zone. Lets say you need to get around someone or just pick up some speed to get through a light. You don't need the car to kick to the lowest gear it can and jump to 4500rpm+, but you want it to get out of the 2k range. If I give it 50% on the gas pedal it will hesitate and then when you give it more because you wonder where the shift is, it says "oh, you want me to actually accelerate" and it drops to the lowest gear finally moving.

Sorry for the rant, but this is the one thing that I hate about this vehicle. Can't wait for the 2014!
Yeah, I experience the same thing. When I brought it into the dealer to see if there was a flash update, I could best describe the issue as the ECU->Engine->Tranny were confused, and we're arguing on who's job it is to get out of this situation.

What I have figured out, it is not so much the transmission as it's the MDS not deactivating early enough sometimes. You can verify this by hitting the 'Tow-Haul' button when you get into this 'confusion' scenario. As long as you're not in overdrive (As the Tow Haul button will down shift you if you are) but it'll immediately disable the MDS and you'll notice the bog/confusion goes away immediately.

If you look at dyno charts for the 5.7: The torque curves on these engines are pretty much flat from 2k to 5k. 320-390 lb-ft is available. That is more than enough pull to grind out any gear on the jeeps.... But that is assuming that MDS is off, and all that power is on hand. If MDS is on, you'll have less than half of that power available. 150-160 lb-ft. (Think how your jeep would work if being pulled by a toyota camry).

My guess is that it is not a transmission issue, but the MDS code should be lightened up a bit -- but is not going to be due to EPA Mileage shenanigans.
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  #31  
Old 07-19-2012, 11:26 AM
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Re: Ready for some tuning? Look here!

Quote:
Originally Posted by ColdCase View Post
There hasn't been an auto transmission since the 727 days that shifted on its own properly all be itself. Most cars out there have one issue or another. None of them can anticipate what you want. Perhaps in 2020 there may be a unit that can read our mind and anticipate.

Sometimes you just have to get off your butt and put some effort into driving.

BTW, have you tried driving a combination of sport and tow/haul mode (if you have them)? I suspect you don't like it because you want better mpg....


When the 8 speeds come out, they will have 8 possible wrong gears, a little worse than the 5 possible wrong gears today...

Well I have had my share of cars and all the other automatics I have had I never once got frustrated about how the vehicle is shifting. Somehow all those other cars knew that if I was trying to accelerate that hey maybe I shouldnt upshift right now so that we can continue to accelerate. Now in the Jeeps mind it wants to try to lug all 5,000lbs up a hill at 1100rpm lol. Thats when I usually say in my mind "this f'ing jeep" then slap the shifter to a lower gear.
As for the tow haul mode I dont have that since I have a V6, but as far as sport mode I do use that pretty often, and I think it helps a little, but still not exactly how I would want it. I wish there was a record mode that will copy the shift points that you do manually, then use those in automatic mode :-) Either way its just one of my gripes on an otherwise excellent vehicle that I can deal with until there is either a fix, tune, or until I drive a 2014 and want one of those lol.
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  #32  
Old 07-19-2012, 11:50 AM
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Re: Ready for some tuning? Look here!

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Originally Posted by JTS97Z28 View Post
As for the tow haul mode I dont have that since I have a V6, but as far as sport mode I do use that pretty often, and I think it helps a little, but still not exactly how I would want it. I wish there was a record mode that will copy the shift points that you do manually, then use those in automatic mode :-)
Oh. See. V6. I can not talk on that, but during the test drive I felt the Pentastar was a bit anemic for the Jeep.

In the case of the v6 I would agree that a 8-Speed would help, but still keep in mind the same issues will arise with the EPA Fuel estimates. Chrysler will tune the transmission to optimize fuel economy for EPA estimates -- which will likely leave it in higher gears longer than desired.

If I we're y'all looking to upgrade, I'd wait for the Diesel, instead of the 8-Speed. Jeep will continue to pull it's v6's from the Chrysler parts bin, and they will never have a Jeepish Torque monster like the ol' 4.0L.
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  #33  
Old 07-19-2012, 12:06 PM
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Re: Ready for some tuning? Look here!

get a TCM tune from B&G. $350
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  #34  
Old 07-19-2012, 12:58 PM
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Re: Ready for some tuning? Look here!

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Originally Posted by JTS97Z28 View Post
Well I have had my share of cars and all the other automatics I have had I never once got frustrated about how the vehicle is shifting.
Both small motor Mercedes vehicles I've owned had the same annoying habit that frustrates you and others here. The Chrysler products I've rented with the Mercedes tranny also seem to have the issue. The Chrysler tranny in my wife's V6 liberty is much better as far as shift points. I think its more of a hold over of Mercedes thinking they know whats best for you regardless of what you think (it is a Mercedes transmission after all). The bigger motor Mercedes with more torque don't seem to have an issue.

I hear the TCM can be reprogramed by a couple tuners out there for better performance. I'm not sure of how much time anyone has spent optimizing the tranny for the small V6, however.
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Old 07-19-2012, 02:51 PM
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Re: Ready for some tuning? Look here!

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Originally Posted by JTS97Z28 View Post
Well maybe the way I explained it came off harsh. My Jeep drives perfectly fine, its just that I personally am not happy with the shift points. Why they would design this thing to shift so early just ruins the driving experience for me. And besides I don't see how bogging the engine can help improve economy. So I wasn't saying my Jeep had a lack of power because it doesnt, it goes just fine if I make it, but during economy minded driving it simply has annoyingly bad shift points.


I absolutely agree that the shift points are horrid and yes the thing bogs itself down unnecessarily. Still very impressed by the v6 and with a little message it can be quite fun to drive.
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  #36  
Old 07-19-2012, 03:41 PM
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Re: Ready for some tuning? Look here!

My v6 in Sports mode shifts real nice. Much better than Auto.
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