How a 5-Speed Auto. Works

Discussion in 'Challenger DIY/Tech Info' started by SRT-Tom, May 12, 2015.

Car Parts
  1. SRT-Tom

    SRT-Tom Well-Known Member Staff Member Super Moderator Article Writer

    Posts:
    7,061
    Likes Received:
    2,174
    Joined:
    Oct 2, 2011
    Location:
    southern New Jersey
    Here is an explanation as to how the manual shift feature works on a NAG1 and WA580 5-speed automatic transmission.

    If you move the shifter to the left side (towards the driver) the transmission will downshift. Conversely, if you move the shifter to the right side (towards the passenger), the transmission will up shift. Moving the shifter either direction (left or right) will take the car out of automatic mode and put it into manual mode (the gear you are in will appear on the LED indicator on the dash and it will l change from D to a 1 thru 5). Holding the shifter to the right for a few seconds throws it back into full auto mode (D on LED indicator).

    While sitting still and idling, moving the shifter to the left will put the car in 1st gear (manual mode). Still sitting and still in 1st gear, moving the shifter this time to the right will put the car in 2nd gear (manual mode, for mud and snow when you don’t want a lot of torque to the rear wheels). You cannot start off in 3rd gear, only 1st or 2nd.

    While driving in full auto mode (D on LED indicator), when you move the shifter to the left, the car will down shift and go into manual mode until you move the shifter to the right and hold it there for a few seconds, or you re-start the car. Both of which will put the car back into full auto mode.

    While driving in manual mode, you can "pre-order" a shift. That is to say, you can move the shifter to the right to go from say 1st to 2nd gear but then quickly move the shifter to the right again to pre-order a 3rd gear shift when the rpms reach a point above stall speed. The transmission won’t let you destroy it. If you attempt to bang it on down to 1st gear while on the freeway doing 70 mph, the transmission will not respond. Same thing for trying to up shift to 5th gear when the car is moving at 5 mph- it’s not going to happen. You can only down shift or up shift within a certain rpm range for that gear, or else the shift will be ignored.

    If, for example, you are in the manual mode traveling down the freeway in 5th gear and you find yourself having to quickly reduce speed, the car will automatically gear down with you as your speed slows. It won’t stay in say 5th gear and let you stall. Likewise, if you are standing still and in 1st gear manual mode and floor it and do not shift into 2nd, then when the car reaches its redline (i.e., max. rpm), it will automatically shift into 2nd gear for you, and on up through the gears. (Note: on newer cars equipped with Sport Mode turned on, you can exceed the redline). Simply put, the transmission won’t let you rev it into infinity and blow the motor. The same thing applies when idling. If you attempt to excessively rev the car while in neutral, the car will most likely go into limp mode to protect itself.

    I hope that this clears up some of the mystery. The manual mode is a lot of fun but like anything, it has a learning curve. Don’t be afraid to try it and experiment. There are safety guards built in. Also, the transmission is electronically controlled and it has a torque capacity of 796 lb-ft- more than enough for the Hemi engines to handle.