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-   -   Is my tranny flashed?? - ooooerrr mrs!! (http://www.jeepgarage.org/f51/is-my-tranny-flashed-ooooerrr-mrs-47375.html)

chudsy 09-12-2012 10:42 AM

Is my tranny flashed?? - ooooerrr mrs!!
 
Hi All,
Been reading around looking for anything which may affect my jeep and I read about the change in 2001 for the transmission which adds the extra OD gear simply by flashing the TCM???
My jeep is at 2500rpm at 90mph - is this enough information to determine is mine has been flashed or should there be something to indicate that it has been done?
If not, should any jeep dealership in the UK be able to upgrade my trasmission?
Best Regards
Paul.

Frango100 09-12-2012 04:50 PM

Re: Is my tranny flashed?? - ooooerrr mrs!!
 
Hi Paul. I think that the dealer should have put a placard to the TCM when the flash has been done. My jeep does 2000 rpm at 120 km/hr in 5th.
When not done, the dealer should be able to do so.
With the flash an extra (5th) overdrive gear will become available, which reduces the noise and the fuel consumption. The TCM will just simply Use an other combination of clutches to accomplish this. (the OD and 2C clutch)

chudsy 09-13-2012 04:12 PM

Re: Is my tranny flashed?? - ooooerrr mrs!!
 
Cheers Frank,
I'll have a look for the placard.
Regards,
Paul.

StoneCold 10-18-2012 04:35 AM

Re: Is my tranny flashed?? - ooooerrr mrs!!
 
Yeah Frank's spot on. There is something they should have put on it, to indicate it's been done.

IIRC, if you say put your Jeep in for a service, if the dealer doesn't see any indication there's been an update, they will automatically flash it for you.

AMSOIL_Dealer 01-01-2013 11:01 PM

Re: Is my tranny flashed?? - ooooerrr mrs!!
 
Is this an option on all post 2001 trans? Or just on the overseas units, since I'm in the USA? Anything to help the mpg.

Frango100 01-02-2013 07:27 AM

Re: Is my tranny flashed?? - ooooerrr mrs!!
 
On the 5-45RFE transmission a simple TCM flash would add a 2nd overdrive gear (5th gear) to the transmission. This was done i believe in 2001 to reduce noise and to increase mpg, after that date all WJs with 5-45RFE came with this software from the factory. Pre date WJs could simply be flashed by the stealer to add that gear and after the flash a placard on the TCM should show this update.
Your jeep has the 42RE transmission and as far as i know there is no possilibity to add any different gear to it.

AMSOIL_Dealer 01-03-2013 10:04 PM

Re: Is my tranny flashed?? - ooooerrr mrs!!
 
Figures, I guess the 5-45RFE are in the 4.7 not 4.0? I was excited I might have been able to have the mod done and save a little fuel.

Frango100 01-03-2013 11:46 PM

Re: Is my tranny flashed?? - ooooerrr mrs!!
 
Yes, the 4.7 comes with the (5)-45RFE and the 4.0 with the 42RE.

AMSOIL_Dealer 01-04-2013 09:35 PM

Re: Is my tranny flashed?? - ooooerrr mrs!!
 
Thank you for the info.


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