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Why do RPM's change when I switch the auto tranny into the manual mode??

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Old Jul 30, 2003 | 01:49 PM
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SteveZzz
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From: Richmond, VA
Question Why do RPM's change when I switch the auto tranny into the manual mode??

I'm curious if anybody knows what's going on in the auto tranny. If I'm just cruising along at an even speed and slide the shifter over into the manual mode, the RPM's change. I'm not doing anything other than moving the shifter. so the tranny shouldn't be shifting to a different gear and I'd expect that the RPM's would stay the same until I change speeds or initiate a shift.
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Old Jul 30, 2003 | 02:17 PM
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The tranny actually shift down for you once you slide the shifter to the manual side. This might not happen on the slower speed, but always happen to me on the freeway crusing speed. I just talked to the tech yesterday and he told me that it's normal.
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Old Jul 30, 2003 | 07:26 PM
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yup, normal as can be. i also notice that if i try to go from 5th to 3rd in manual mode with my foot on the gas, it shifts to 4th and then i have to keep down shifting to get it to 3rd. if i take my foot off the gas, all i have to do is tap down twice to get to third. hmmm......
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Old Jul 30, 2003 | 08:18 PM
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From: Phoenix
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popping to manual generally drops one gear- like 5 to 4 when you are on the highway.
it does not go to 1st from 2nd ever, except at a stop.
seems like this is the way it was programmed.
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Old Aug 3, 2003 | 10:24 PM
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I found that whenever the I switch from full auto to the manual mode that it keeps the same gear that it was in unless I'm in 5th. If I'm in 5th, it will downshift to 4th when I switch over. I heard that the purpose for this is so that if you need to get into a passing gear it will get there without having to switch to manual and manually downshifting. (Two shifts vs. one shift) Just push it to the side to get out of overdrive then put it back into to full auto.

The full auto mode on the 5AT is an adaptive transmission and in most cases it can tell when you want to pass and it will use the right shift algorithm for this. If you want to be sure it downshifts, just push it to the side.
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Old Aug 3, 2003 | 10:41 PM
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Originally posted by paintballjunky
yup, normal as can be. i also notice that if i try to go from 5th to 3rd in manual mode with my foot on the gas, it shifts to 4th and then i have to keep down shifting to get it to 3rd. if i take my foot off the gas, all i have to do is tap down twice to get to third. hmmm......
When manually shifting the 5AT you don't want to ease off on the accelerator when upshifting. (Something I was doing when I switched from a manual to the 5AT.) When downshifting more than one gear, I find that it usually shifts faster while easing off the accelerator or braking. Ease off the accelerator and tap down the shifter a few time quickly and it will do go from 5th to 3rd right away. It shifts down painfully slow if you want to go down more than one gear while still accelerating.
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Old Aug 4, 2003 | 01:29 AM
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I noticed exactly what you're saying, when shifting over to manual mode there is a definite rpm change even at slower speeds. I know that I have never been able to switch over to manual and have fifth gear show up, so it is definitely shifting down from fifth to fourth but there is also a lockup torque converter happening at fourth gear and fifth gear in this transmission may be where noticing that disengage also at slower speeds
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