Downshifting with an AT

Jordo!

Unless it explicitly says not to in the owner's manual (which if it does, I missed it), provided you are at the correct speed (< 5 mph and coming to a stop), why not?

The very fact that you can suggests it is not inherently stressful on the trans, provided road speed and engine speed are appropriate -- the ECU will not allow an up shift if the engine speed will be too low, and although I haven't tested it, it probably won't let you downshift such that you would rev too high.

To the OP: It all depends on how much extra throttle would be needed to optimally match engine speed to gear. If you are already about at the right speed, there won't be much if any blipping.

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