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Discussion Starter #1 (Edited)
Hey guys first of all i want to apologize for any grammatical erros english is not my first language, now to the problem i have a 2007 charger rt that seems to have issues downshifting when i use the autostick mode, the car upshifts fine (sometimes has a small delay but it shifts up fine and smooth) but when i try to downshift it wont let me i sometimes have to push the stick left rough and hold it there for it to downshift other times i have to push it to the left several times until it downshifts, and when it does it feels a bit rough for example if im driving at 35mph in third and i try to downshift to second it wont let me, but if im in 4th at the same speed and downshift it goes to third just fine.

the car does have 200,000 miles and i've done all its services, the engine seems healthy no lifter noise from what i can tell yet, the car doesn't have cats and its a straight pipe with magnaflows where the resonators used to be (bought it this way), the car does throw some codes but nothing that indicates the transmission its mostly obd2 codes due to no cats.

if you guys had anything similar to this or this exact issue would appreciate to know what it was.
 

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The TCM (transmission control module) controls the transmission. Even in AutoStick, you're signaling to the TCM that you want to shift up/down but it's the TCM that decides if/when it will do it. The 2007 Chargers do not have rev-matching to match the engine RPMs to the selected gear (like when downshifting). So you have to use the accelerator to match the engine RPMs to the downshifted gear. If you don't, the TCM will wait until the car's speed is reduced to an acceptable speed ... for the next gear ... before it downshifts.
If you're getting diagnostic trouble codes (like P2779 - Autostick downshift switch performance) the expected switch state is not being correctly sensed by the Shift Lever Assembly.
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Discussion Starter #3
The TCM (transmission control module) controls the transmission. Even in AutoStick, you're signaling to the TCM that you want to shift up/down but it's the TCM that decides if/when it will do it. The 2007 Chargers do not have rev-matching to match the engine RPMs to the selected gear (like when downshifting). So you have to use the accelerator to match the engine RPMs to the downshifted gear. If you don't, the TCM will wait until the car's speed is reduced to an acceptable speed ... for the next gear ... before it downshifts.
If you're getting diagnostic trouble codes (like P2779 - Autostick downshift switch performance) the expected switch state is not being correctly sensed by the Shift Lever Assembly.
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hey thanks for the reply!, do you know what year they added rev matching? i also have a 2008 that lets me downshift thats why i thought the 2007 charger had issues with its transmission since i was comparing it to the 2008.

however i did forget to mention this and this is completely my fault, if im at a red light and i switch it to autostick mode i can upshift to second and sometimes it wont let me downshift keep in mind this is on a complete stop the car will go to second and sometimes i have to fight with the stick to get it to go back down to first. i do remember trying different things even letting go of the pedal to downshift and it just wouldnt work, sometimes it does downshift.
 

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I don't think rev-matching was added until the 2015+ models. If you're having problems with AutoStick when stopped then the switch in the Shift Lever Assembly could be the problem. The NAG1 will let you select 1st gear or 2nd for take-off from a standing start. When switching from full auto ("D") to AutoStick, or to 2nd or 1st gear ... when stopped ... it may take a couple of taps to switch gears. Probably depends on how long you hold the tap. My car sometimes requires the double tap, when stopped, but always shifts with a single tap while driving.
You said the check engine light is On and you have some diagnostic code logged. Use your scanner to check which codes are logged and see if any of them are related to the transmission.
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Discussion Starter #5
I don't think rev-matching was added until the 2015+ models. If you're having problems with AutoStick when stopped then the switch in the Shift Lever Assembly could be the problem. The NAG1 will let you select 1st gear or 2nd for take-off from a standing start. When switching from full auto ("D") to AutoStick, or to 2nd or 1st gear ... when stopped ... it may take a couple of taps to switch gears. Probably depends on how long you hold the tap. My car sometimes requires the double tap, when stopped, but always shifts with a single tap while driving.
You said the check engine light is On and you have some diagnostic code logged. Use your scanner to check which codes are logged and see if any of them are related to the transmission.
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theres no tcm related codes the thing is i have an 08 rt aswell and lets me downshift gears down to first just fine i've even matched the revs and speed on both cars to see the difference and noticed the 07 has issues downshifting when the 08 downshifts just fine.

so you think its the switch in the shift level thats broken? i will try and diagnose more before i switch the level, could the transmission oil be the issue? the car does have 200,000 miles and im not sure if they ever replaced the oil and filter.
 

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With that many miles, and no history on the maintenance, I would definitely change the fluid & filter as the first course of action.
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