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-   -   2012 6 speed auto (http://www.jeepgarage.org/f73/2012-6-speed-auto-29226.html)

walterhudson 10-01-2011 11:51 PM

2012 6 speed auto
 
Does anyone know the exact transmission gear ratios of the 6 speed auto compared to the 2011 5 speed? I'm wonderig if the performance will improve.

sined240 10-02-2011 06:35 AM

Re: 2012 6 speed auto
 
The gear ratios are EXACTLY the same, just that they were programed to run as 1-2-3-4-5-6 and the 5-speed was made to run 1-2A(2B during downshift)-3-4-5. Towards the bottom of the link below, it shows the same ratios for 545RFE and 65RFE. It's worthy to note that the newly updated flash software makes the 545RFE into a 6 speed as well.

http://www.allpar.com/mopar/transmissions/545RFE.html

kaww2 10-02-2011 05:05 PM

Re: 2012 6 speed auto
 
Is the update available for the 6 cyl or is it just for the hemi?

sined240 10-02-2011 05:37 PM

Re: 2012 6 speed auto
 
just for the tranny mated to the hemi...

walterhudson 10-03-2011 12:17 AM

Re: 2012 6 speed auto
 
Quote:

Originally Posted by sined240 (Post 492985)
The gear ratios are EXACTLY the same, just that they were programed to run as 1-2-3-4-5-6 and the 5-speed was made to run 1-2A(2B during downshift)-3-4-5. Towards the bottom of the link below, it shows the same ratios for 545RFE and 65RFE. It's worthy to note that the newly updated flash software makes the 545RFE into a 6 speed as well.

http://www.allpar.com/mopar/transmissions/545RFE.html

Thank You

franco1961 10-03-2011 02:07 AM

Re: 2012 6 speed auto
 
"newly updated flash software makes the 545RFE into a 6 speed as well"
You sure?
Which software?

sined240 10-03-2011 05:43 AM

Re: 2012 6 speed auto
 
most likely,
http://www.wk2jeeps.com/tsb/tsb_wk2_1803511.pdf

do a search, its been exhausted. there has been better information posted before...

ColdCase 10-03-2011 06:02 AM

Re: 2012 6 speed auto
 
Quote:

Originally Posted by franco1961 (Post 493359)
"newly updated flash software makes the 545RFE into a 6 speed as well"
You sure?
Which software?


Functionally yes, except that you won't see 6 displayed in the EVIC. Some April builds and all 2011s built May or later have the updated soaftware. There is a TSB that corrects harsh shifts among other things that includes the update. TSB 18-035-11 I think

franco1961 10-03-2011 10:21 AM

Re: 2012 6 speed auto
 
I think this TSB will not change the 1-2A(2B during downshift)-3-4-5 into 1-2-3-4-5-6.
Just make the changing smoother and with right rpms.
Am wrong?

ColdCase 10-03-2011 11:19 AM

Re: 2012 6 speed auto
 
The TSB makes a software change to the 2011 to provide the same function as the 2012. There is suppose to be a slightly different torque converter in the 2012 that may also have been a running 2011 change. The bottom line is that the difference between a 2011 with TSB and 2012 is hard to tell, if any (except for the EVIC display and what happens when you left tap out of D).

from : http://www.allpar.com/mopar/transmissions/545RFE.html

" The next six speed derived from the 545RFE was the 65RFE, initially used with V8 versions of the Ram 1500, Durango, and Grand Cherokee. The 65RFE does not have six forward gears in regular automatic mode, only in ERS/AutoStick mode; it is essentially a software and name change, which allows people to reach the “prime” gear via ERS rather than kickdown. An internal Chrysler communiqué to dealers summarized the change in a similar fashion. "

For example, one scenario is a before TSB 2011 operating in D; left tap the shifter the EVIC displays 5 but there is no gear change, you stay in OD 2, so called 5th. You can then tap down 4-3-2B-1 (total 5). After the TSB tap left on the shifter and the EVIC displays 5 but the transmission also shifts out of OD 2 to OD 1 (so you are now in so called 4th), then tap down 3-2B-2A- 1 (total of 6 ratios). In a 2012, when you left tap from D, the EVIC will display 6 and the transmission remains in OD2 (so called 5th or 6th depending on your POV). Then you can tap down through 4-3-2B-2A-1 (total of 6).

So the "6 speeds" is basically a marketing thing, but there are several other important programing improvements in the TSB that also get picked up in the 2012s making for better driving satisfaction for most.

jmpdev2020 10-05-2011 09:29 AM

Re: 2012 6 speed auto
 
Quote:

Originally Posted by ColdCase (Post 493470)
The TSB makes a software change to the 2011 to provide the same function as the 2012. There is suppose to be a slightly different torque converter in the 2012 that may also have been a running 2011 change. The bottom line is that the difference between a 2011 with TSB and 2012 is hard to tell, if any (except for the EVIC display and what happens when you left tap out of D).

from : http://www.allpar.com/mopar/transmissions/545RFE.html

" The next six speed derived from the 545RFE was the 65RFE, initially used with V8 versions of the Ram 1500, Durango, and Grand Cherokee. The 65RFE does not have six forward gears in regular automatic mode, only in ERS/AutoStick mode; it is essentially a software and name change, which allows people to reach the “prime” gear via ERS rather than kickdown. An internal Chrysler communiqué to dealers summarized the change in a similar fashion. "

For example, one scenario is a before TSB 2011 operating in D; left tap the shifter the EVIC displays 5 but there is no gear change, you stay in OD 2, so called 5th. You can then tap down 4-3-2B-1 (total 5). After the TSB tap left on the shifter and the EVIC displays 5 but the transmission also shifts out of OD 2 to OD 1 (so you are now in so called 4th), then tap down 3-2B-2A- 1 (total of 6 ratios). In a 2012, when you left tap from D, the EVIC will display 6 and the transmission remains in OD2 (so called 5th or 6th depending on your POV). Then you can tap down through 4-3-2B-2A-1 (total of 6).

So the "6 speeds" is basically a marketing thing, but there are several other important programing improvements in the TSB that also get picked up in the 2012s making for better driving satisfaction for most.

I had the TSB done about two weeks ago and immediately noticed smoother shifting patterns as well as decreased delay in throttle response when accelerating at highway cruising speeds.

Per your example above for the 2011 after TSB, should I feel the downshift from D to OD1? Tried it several times at highway cruising speeds but did not feel it. I can feel 5 to 4.

ColdCase 10-05-2011 11:22 AM

Re: 2012 6 speed auto
 
Quote:

Originally Posted by jmpdev2020 (Post 494394)
I had the TSB done about two weeks ago and immediately noticed smoother shifting patterns as well as decreased delay in throttle response when accelerating at highway cruising speeds.

Per your example above for the 2011 after TSB, should I feel the downshift from D to OD1? Tried it several times at highway cruising speeds but did not feel it. I can feel 5 to 4.


It is hard to tell what ratio you are actually operating in as the trany does not directly provide the info and the gear selector is simply a limit, not direct control. There is also the operation of the TC lockup that muddles things.

My late April 2011 build works like this: Drive a constant 70 mph (closed road course) maintaining a constant throttle and watch the tach as you left tap the gear selector. You should see an immediate increase in rpm (500-800 rpm I think) and 5 displayed by the EVIC. The rpm may drop down a bit (100 rpm or so) when the TC locks but still be higher than the starting point.

Prior to the TSB, after taping the gear selector the EVIC would display 5 but there would not be an immediate rise in rpm (perhaps the 100 rpm due to the TC lock/unlock)

Under the same conditions, after the first tap, the 2012 will just display 6 in the EVIC , the second tap will function the same as my 2011 above.

There is a thread somewhere with more details, later I'll see if I can find it.

See this thread for the experience of some others:

http://jeepgarage.org/showthread.php?t=26955

starting from 35MPH
While coasting, tap to left displays 5, no change in rpm (1000), applying throttle will cause some shifting (1500-2000 rpm), but display still indicates 5 as top gear.

tap down to 3 and maintain speed- 2000rpm
tap to 2 - 2300
tap to 1 - 4100 (seems same as above)

downshifting from 70 mph starting in D at 1700 rpm
tap to 5 maintain speed - initially 2200 then drops to 2000 (probably something to do with torque converter locking up)
tap to 4 2700... then got busy with traffic on this closed course

75mph in D is 1900rpm

That sounds like six ratios available on down shifting (EVIC labeled D-5-4-3-2-1), plus some variation due to TQ lock.

If you divide the 70 mph rpms by 2 to make it equivalent to the 35mph rpm numbers for a given speed, the motor turned 4100, 2300, 2000, 1350, 1100, and 950* rpms..

*850 rpm (D) may also had TQ locked, so apples to apples rpm may closer to 950 rpm w/o TQ lock.


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