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-   -   2012 Transmision V6 shifting at 25mph (http://www.jeepgarage.org/f109/2012-transmision-v6-shifting-at-25mph-47178.html)

Fredg369 09-07-2012 02:05 PM

2012 Transmision V6 shifting at 25mph
 
Hi All!
Just bought a 2012 GC.
Just wondering if this is happening to anyone else.

When driving at around 25mph going down the street, when I lift off the gas,
It feels like the vehicle is holding on to the gear its in instead of up shifting. Then it shifts and glides freely. If I go right to the break this don't happen.

I only have a little over 200 miles on it.
Think the TCM is still learning or is this a real problem?

REALM 09-08-2012 08:02 AM

Re: 2012 Transmision V6 shifting at 25mph
 
I have that issue every now and then... Maybe once every couple of weeks, I think the speed and condition of when I let off the gas has to be right. 38K on my 2011.

Fredg369 09-09-2012 07:48 PM

Re: 2012 Transmision V6 shifting at 25mph
 
I can't take it no more its gona have to go in for service.....wtf...little over a week old.

subbie09 09-09-2012 08:19 PM

The TCU is thinking you are going to hit the gas again under heavy load, therefore it is holding the gear in anticipation, and after a certain time you dont it will shift.

Sent from my SAMSUNG-SGH-I997 using Tapatalk 2

Fredg369 09-09-2012 11:16 PM

Re: 2012 Transmision V6 shifting at 25mph
 
Quote:

Originally Posted by subbie09 (Post 681470)
The TCU is thinking you are going to hit the gas again under heavy load, therefore it is holding the gear in anticipation, and after a certain time you dont it will shift.

Sent from my SAMSUNG-SGH-I997 using Tapatalk 2


So is this normal...will I just be wasting my time taking it back?:confused:

subbie09 09-10-2012 07:50 AM

Re: 2012 Transmision V6 shifting at 25mph
 
more than likely yes. The logic of the TCU is your going to hit the gas again to try to accelerate, and the load of the vehicle is at a certain level, why should it switch to a higher gear, only having to downshift again in a few seconds?

Fredg369 09-10-2012 09:40 AM

Re: 2012 Transmision V6 shifting at 25mph
 
Ok....I came up with this logic for driving it.
I have to accelerate enough to get it into 3rd gear going down a city street then coast.
It don't like 2nd gear at all at 25mph and it seems the gear runs short while coasting.
Now this all works good till some1 is in front of me. Then I have to either fall back far enough to accelerate lightly or use the auto stick to put it in 3rd manually.
This is all stupid...I read this trans has been around since 1995 on Mercedes-Benz's, are you gonna tell me MB drivers put up with this kind of shifting and dragging a gear...BS!
Transmission design from 1995 what a joke....Its only 2 yrs in and the 2013s are getting a 6 speed auto and the 2014s are getting a 8 speed auto...2011 & 12 owners are screwed.They rushed the vehicle into production without a capable transmission. The 5 speed is gona be the weak point, especially how hot this vehicle runs. It will be nothing but trouble...heat + trans = shit sandwich......mother f'ers!
I'm just venting thanks.

subbie09 09-10-2012 10:19 AM

Re: 2012 Transmision V6 shifting at 25mph
 
whatever. Can't please everyone.

Jeep_addicted 09-10-2012 01:31 PM

Re: 2012 Transmision V6 shifting at 25mph
 
Here is the how TCU works:

foward speed + pedal pressure to determine what operation parameter.

If you are on the open road and allow the car to accelerate it will continually upshift once it reachs the speed that is programmed to upshift at.

If you are in slow traffic or stop and go traffic it will hold 1st gear as it assumes that your forward speed is low and not increasing therefore I must hold the gear because you are in condition that require low speed.

Granted the transmission could be a little snappier under most conditons it operates smoothly and gets the vehicle moving with little pedal pressure.

Here's what I do sometimes when taking off from a stop light I give it just enough throttle to roll forward then I maintain that same pressure and before you know it the car has gone throught the gears and it is doing 55mph.

Fredg369 09-10-2012 02:26 PM

Re: 2012 Transmision V6 shifting at 25mph
 
My be I'm not explaining right.
If I let off the gas and the vehicle binds-up, to me its ready to shift and should, not drag.
Not being at the shift point is one thing don't shift but don't hold the vehicle back if I want to coast. Its like using the trans to come to a stop (Trans-breaking)....That can't be good for the drive train.

JTS97Z28 09-10-2012 06:27 PM

Re: 2012 Transmision V6 shifting at 25mph
 
I have found that the overall shifting of the V6 is very poor. I have a 12 Overland and so far thats my biggest gripe. Nothing like trying to accelerate up a slight incline with cars behind you and it up shifts and puts you at 1,000rpm trying to accelerate. My wifes sees me slap the stick to manually downshift it back. Pisses me off lol. Im praying they come up with some sort of reflash for the shifting program.

Fredg369 09-10-2012 06:40 PM

Re: 2012 Transmision V6 shifting at 25mph
 
Quote:

Originally Posted by JTS97Z28 (Post 681836)
I. Im praying they come up with some sort of reflash for the shifting program.


AMEN!!!! to that.


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