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Old 07-11-2006
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TimHolt TimHolt is offline
DieselRam's Tranny Guru
Join Date: Oct 2003
Location: Arlington Texas (Mid cities DFW)
Posts: 3,804
Default Re: Dodge 47RE Shift Help!

Its not a problem with the trans but rather the command from the computer. 4th gear is a direct command just like the lockup command. With some mods, if not most, the defuel RPM has been raised as a result from the mods. The 4th shift is supposed to happen at the point of defuel and allow the shift and then bring power back on. Mods to the engine allows the RPM to be reached faster than the expected defuel event for the shift. What happens then instead of having a soft defuel, it runs to the limit, defuels quickly and lays off waiting for the trans command for 4th gear to catch up. A better solution would be for the mods to not defuel at all, or defuel at about 3400 to 3500 RPM and have the shift made under full power. But because of liability issuses the boxes wont exceed the factory RPM defuel point but just take it to the edge of it. It creates a timing problem between engine performance and shifts. Using the switches to override the lockup and 4th gear commands is a simple and quick way to get around the issue without overrevving the engine. Finding a way to overwrite the software to make the trans shift into 4th gear earlier would be better. But thats not likely to happen, its just hasnt been on the front burner of the makers of mod boxes.
The mods I talk about here is for information purposes only. I experiment on my own vehicles but do not endorse the modifications that I make to my vehicles to be used on others. If you use this info that I talk about, you use it at your own risk and responsibility.

03 Dodge 4X4 quad cab Dually. Two travel trailers, 1 cargo trailer. Lots of ham radios. Call sign N5ZYK Tech class. On 28.300 to 28.500 around 10:00 AM to 2:00PM every sunday.
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