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Not sure of a better title, but Ill try to explain what I am experiencing as best I can. I've driven a few different automatic transmission cars with a manual mode. Normally when down shifting (to slow down) it appears to automatically bring the engine rpms up to match the speed and create a nice smooth downshift.

I notice that when I downshift in this car specifically (most apparent from 3rd -> 2nd gear) that this does not happen and I experience a "jerking" motion as the car rapidly decelerates as the engine rpms match the speed.

If I press the accelerator even just a little bit, it seems to smooth this experience out and eliminate the "jerk" forward.

Is this a common issue? or is there something I should be concerned about?

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up vote 1 down vote accepted

When driving your vehicle in Drive, all gear shifting is done automatically by its control system. The control system would be set out to engage, up or down, with a soft engagement. When you are selecting manually the system would engage the gear and adjust the engine speed usually abruptly. This applies to a great many autos and is the harshness you discribe. Using the gearbox, auto or manual, as a brake is not a great idea. Try slowing with the brakes and then selecting the lower gear. You should find the harsh down change will greatly disappear.

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Thanks for the response. Its not something I do regularly, nor do I plan to. Just an observation ive made over time. Good to know its not abnormal. –  gh123man Dec 6 '13 at 13:39
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