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-   -   Trans Flash For Extra Gear (http://www.jeepgarage.org/f204/trans-flash-for-extra-gear-65298.html)

dons2346 09-10-2013 10:29 PM

Trans Flash For Extra Gear
 
This is a quote from Wiki concerning the '99 trans:

"The 45RFE and 545RFE automatic transmission in the WJ was notable. It included three planetary gear sets rather than the two normally used in a four-speed automatic. This gave it six theoretical speeds, and it would have been the first six-speed transmission ever produced in volume, but it was programmed to only use five of these ratios. Four were used for upshifts, with a different second gear for downshifts. Although five of the six ratios were used, Chrysler decided to call it a "4-speed automatic". In 2001, the programming was changed to make use of all six ratios. Rather than have six forward gears, the transmission was programmed to act as a five-speed with the alternate second gear for downshifts. The rpm at 70 miles per hour (110 km/h) on a 545RFE is 2000 rpm, 200 rpm less than the 45RFE programming. 1999 and 2000 model year WJ owners can have their 45RFE transmission's programming flashed to enable the extra gear as both transmissions are physically the same."

Has anyone had the programming changed to gain the extra gear?

Frango100 09-11-2013 02:48 AM

Re: Trans Flash For Extra Gear
 
I think that only someone who never took the jeep to a stealer from 99 up until now, could still have the 4 speed programming in the TCM.
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Milous 09-11-2013 03:52 AM

Re: Trans Flash For Extra Gear
 
http://www.wjjeeps.com/tsb/tsb_wj_1802501.pdf

dons2346 09-11-2013 10:34 AM

Re: Trans Flash For Extra Gear
 
This is a new Jeep for me and I know the previous owner didn't have it flashed. The wife backed into a van damaging the right rear of our '00 which totaled it out. Bought this one to replace it as I don't want to use the '14 to haul crab bait and fish in.

Looks like I will have to go to the stealer if I want to lower the RPM by 200. Other than that, is there anything else to be gained?

Frango100 09-11-2013 11:27 AM

Re: Trans Flash For Extra Gear
 
The second overdrive gear (fifth gear) adds in better mpg and lower noise, that's it. When the flash has been performed, it should be mentioned on a modification placard on or close to the TCM.

dons2346 09-11-2013 10:43 PM

Re: Trans Flash For Extra Gear
 
Got it.

hoffmanestates 09-18-2013 08:09 PM

Can dealer tell me if its been flashed?

Sent from my LG-P999 using Tapatalk 2

Frango100 09-18-2013 08:41 PM

Re: Trans Flash For Extra Gear
 
Quote:

Originally Posted by hoffmanestates (Post 895926)
Can dealer tell me if its been flashed?

Sent from my LG-P999 using Tapatalk 2

Long time not seen overhere.
Dealer should be able to tell you, a placard on or near the TCM could also tell you if the flash has been performed and you could count the gears to see if it has fifth gear or not. Just look at the tacho to see when it shifts (or let a passenger look at it when you drive, to keep it at the safe side:D)


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