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z51vette
01-13-2007, 12:02 AM
:dunno: Here is a question for all of you AT guys. Not sure if this is a feature on the 07 or has been present since 04 or if it is normal operation at all. When the transmission is in manual gear selection mode, and you are in high gear lets say 5th or 6th then you floor the throttle all the way (past the clicker) down to the floor is it supposed to downshift into the lowest possible gear by itself. I found this out today while driving about 30 mpg in 5th or 6th when I floor it, it goes to 2nd or the lowest gear that doesn't over rev the engine.

Is this normal?

Andre
01-13-2007, 08:10 AM
It is normal. It is not a real manual mode. It will upshift on its own too if it thinks you're revving too high. Try leaving it in 1st gear on a take-off, and near the redline it will shift to 2nd on its own.

z51vette
01-13-2007, 11:18 AM
It is normal. It is not a real manual mode. It will upshift on its own too if it thinks you're revving too high. Try leaving it in 1st gear on a take-off, and near the redline it will shift to 2nd on its own.

That's understandable. Because otherwise damage will occur and that is the only reason in theory why you would want the electronics to shift for you. To prevent damage. But why would it downshift especially to such a low gear with no damage potential instead of gradually building speed. I mean it goes from 3,000 to 6,000rpm by itself. Obviously if you are in 6th and going 60mph and come to a stop it would have downshifted to 2nd by the time you stop. But I don't see a reason for it to downshift from 6th to 2nd when you floor it in manual mode. And this only happens when you go past the resistance point (button or clicker) with the pedal to the floor.

Did you actually try doing this with your car to see if the same thing happens?

Andre
01-13-2007, 11:57 AM
That's understandable. Because otherwise damage will occur and that is the only reason in theory why you would want the electronics to shift for you. To prevent damage. But why would it downshift especially to such a low gear with no damage potential instead of gradually building speed. I mean it goes from 3,000 to 6,000rpm by itself. Obviously if you are in 6th and going 60mph and come to a stop it would have downshifted to 2nd by the time you stop. But I don't see a reason for it to downshift from 6th to 2nd when you floor it in manual mode. And this only happens when you go past the resistance point (button or clicker) with the pedal to the floor.

Did you actually try doing this with your car to see if the same thing happens?

Yes, my car does this, and it is normal. The clicker is the downshift button.

If you're in a range where 2nd gear can be downshifted to for passing, it will downshift to that gear. If you were going faster, then it would downshift to 3rd or 4th. It's trying to downshift to as low a gear as possible to give you as much power as possible for passing.

And I disagree with you about damage occuring - the car has a rev-limiter, and won't go over the redline, just like with a manual transmission. I wish they would make manual mode completely manual, for both upshifting and downshifting.

z51vette
01-13-2007, 12:10 PM
Yes, my car does this, and it is normal. The clicker is the downshift button.

If you're in a range where 2nd gear can be downshifted to for passing, it will downshift to that gear. If you were going faster, then it would downshift to 3rd or 4th. It's trying to downshift to as low a gear as possible to give you as much power as possible for passing.

And I disagree with you about damage occuring - the car has a rev-limiter, and won't go over the redline, just like with a manual transmission. I wish they would make manual mode completely manual, for both upshifting and downshifting.


That's the key word here. The clicker is the downshift button. That's what I knew, I just didn't think it would be active in manual mode. Thanks.

Rev-limiter or no rev-limiter, if you are driving for extended periods of time at or near redline it is not good for the engine/tranny especially with the limiter kicking in constantly. Believe it or not, I've seen people drive at redline with the limiter kicking in for extended periods of time.

Andre
01-13-2007, 01:04 PM
Rev-limiter or no rev-limiter, if you are driving for extended periods of time at or near redline it is not good for the engine/tranny especially with the limiter kicking in constantly. Believe it or not, I've seen people drive at redline with the limiter kicking in for extended periods of time.

Yes, well, there will be idiots I guess, but those idiots could do the same on a manual too. Maybe it's worse on an auto trannie...