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Discussion Starter #1
I have a 2009 Malibu LTZ (6 speed). I had it for two days and it forgot how to shift. I brought it back to the dealer, and after several calls to many techs, they had to do a "quick learn" to reprogram the computer. I drove it a week, and it forgot how to shift again.

Has anyone had or even heard of this problem?
 

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ours seems to hold into gear too long sometimes. have to let off the gas for it to shift. I havn't checked it out yet. but it is rather annoying
 

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Mine would downshift to 5th going down a nice steep hill at 65mph... and it would try to downshift and lose power when going up my driveway (a steep hill) at 10mph. And the best part: if I put it into manual mode (so it will shift correctly going up hills), and I let it get to 2100rmps, it STILL shifts itself to the next higher gear and then loses power! The dealer told me this was "normal" since the manual shifting won't let the car get too far out of "legal range" before doing what it needs to ... but the book only says it will shift down (like when you are stopping). I thought one of the main reasons for having the manual was to control shifting when you were towing or pulling hills so you could get more power...
 

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Mine would not leave first gear.. And would not change to manual mode.. You could put it down there but the display wouldnt change or anything.. I got it back to the dealer and they put a new battery and replaced the computer and all is well
 

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Mine would downshift to 5th going down a nice steep hill at 65mph... and it would try to downshift and lose power when going up my driveway (a steep hill) at 10mph. And the best part: if I put it into manual mode (so it will shift correctly going up hills), and I let it get to 2100rmps, it STILL shifts itself to the next higher gear and then loses power! The dealer told me this was "normal" since the manual shifting won't let the car get too far out of "legal range" before doing what it needs to ... but the book only says it will shift down (like when you are stopping). I thought one of the main reasons for having the manual was to control shifting when you were towing or pulling hills so you could get more power...
Upshifting at 2100 in M is not normal....Yes, that's true what they say about the legal range, but it should really be somewhere near redline. Otherwise it should hold the gear low or high provided that the rpm is within that range.
 

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The 6 speed is junk as noted many times in this forum. Do your homework, GM!!!!

Last night on the highway at 65mph I needed to surge ahead in traffic to avoid a situation and the tranny would not downshift for extra power. At 65 there is no throttle response in 6th gear.

Good thing this car has good looks because people aren't buying based on the mechanicals.

Another thing: why does it takes two seconds for the manual shifts to occur? I hit the button and count to two before the gear changes. I don't expect Ferrari F1 response time but this button shifter is very slow.
 

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I'm spending some time doing tuning on the TCM to get mine better. I'll report back if it helps or not.
 

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I'm spending some time doing tuning on the TCM to get mine better. I'll report back if it helps or not.
As I know at least one popular company who does it often with the G6 crowd, 3.6L/6-spd tuning included, I was always tempted with my '09 2LT. Overall, the shifting was fine, but also annoying. Then again, I also had a pretty bad shuddering/rumble issue that was never figured out, so that could skew my view.

Of the many 2.4L/6-spd and 3.6L/6-spd cars I've driven, I've been very pleased with the responsiveness and feel. Some of us have had issues, clearly, but it's not the norm...such as in this case. I'd venture to say it's a computer issue, clearly, or some other strange system foible that's making it throw fits. Mine, in the 3.5 months I had it, had strange days and could be 2 different cars powertrain wise depending on the hour, but I never had issues with the shift points, etc. not operating at the right times.

If the dealer is in contact with GM, etc. clearly something is up, and at least they realize it. The problem is just, specifically, that "what" and how the heck to fix it.
 

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I'm spending some time doing tuning on the TCM to get mine better. I'll report back if it helps or not.
That s the only way to get any GM product to shift well. It s probably the torque management put into the trans via computer that causes the delay in order to protect the trans.. Thats being said, I think the 6 spd is one of the best functions of this car.Mine works perfect and I m very fussy with that. I usually get my ECM/TCM retuned by an aftermarket tuner but this car being a lease I will leave it alone.
 

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That s the only way to get any GM product to shift well. It s probably the torque management put into the trans via computer that causes the delay in order to protect the trans.. Thats being said, I think the 6 spd is one of the best functions of this car.Mine works perfect and I m very fussy with that. I usually get my ECM/TCM retuned by an aftermarket tuner but this car being a lease I will leave it alone.
Agreed on both accounts. Many of them change dramatically with a "tune", still staying full well within and even improving durability stats at the same time. I generally liked the 6-spd performance of my Malibu, but it had problems as well, so I never got a 100% view of what it should ideally be, without the random shuddering, bogging, stuttering on deceleration and shaking, etc. One thing I for sure LOATHED was how it worked in stop and go traffic, clunking and thunking, and just feeling bizarre and confused/unrefined--at least leaving it in full auto mode. Of course, it also could have been effected further by whatever was causing my other issues.

On the other hand, I absolutely love every last thing about the 6-spd performance in my new G8, admittedly with a big V8. Nothing has yet to bug me about it, even though I am getting both the engine and trans computers retuned shortly...just because. Crispen things up further, completely revise all of the engine controls to better utilize premium and boost mileage, etc. There's always a lot left on the table for improvement/change with GM programming--but there are most definitely reasons for everything being the way it is, OEM. From the amount of torque management and spark retard to the lazy downshifting, etc. Thanks for tuners, we can still fine tune a lot of things to be exactly how we want.

Curious to see a re-tuned Malibu powertrain...even though it has already been done with the G6 3.6L/6-spd, and the improvements very liked.
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Back on topic...

redhorse - Any update on your issues, yet?
 

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Discussion Starter #11
Nothing resolved yet. The dealer said is was shifting "within parameters". I had written down everything it was doing and on the service sheet they said it was normal for it to shift if it "needed to" while in manual mode. I picked the car up after hours so no service people were there. I need to call and ask why shifting up at 2100rpm while in manual mode is "normal". I think they may have misread that.

I had two other issues. On the plus side, they got the pulling problem fixed. They had to do a X tire rotation on a new car... what does that say about the tires I wonder? There is a bad mildew/musty smell coming from the cowling; they have tried to work on that three times to no avail. They keep spraying something on it that doesn't work.
 

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I just looked at the TCM file and all the manual mode shift points are set at 318mph...even at 0% throttle on my wifes 09 V6 with 6speed. Where are you located at? Can the dealer see that the trans is in M mode with a tech 2? The trans should not upshift in M mode unless you tap it up. The rev limit is set at 7K rpm on a stock V6, so it should climb up that far and not shift, no matter what the throttle position is. Is your car storing any codes?
 

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Discussion Starter #13
I just looked at the TCM file and all the manual mode shift points are set at 318mph...even at 0% throttle on my wifes 09 V6 with 6speed. Where are you located at? Can the dealer see that the trans is in M mode with a tech 2? The trans should not upshift in M mode unless you tap it up. The rev limit is set at 7K rpm on a stock V6, so it should climb up that far and not shift, no matter what the throttle position is. Is your car storing any codes?
I'm thinking about having my husband record (via digital camera) the tack and steering wheel so they can see that it upshifts on its own at 2100rpm (yesterday, it was 2200). What happened the first time I took it in (I believe) is that it lost all of its codes and they had to reprogram it. Makes me wonder why that happened... and highly suspect that is has happened again. They were getting an error message via the diagnostics the first time; now they get nothing.
 

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I have a 2009 LT with the 2.4L 6 speed transmission with just 75km on it.
I was driving in the city at just under 50 k/h ,as I lightly excelerated the engine revved up and then went hard into gear. I'm going to drive it for a few more days until I figure out what speed and circumstances this happens at , then I'll take it in to the dealer.
Anyone else with this problem?
 

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Discussion Starter #15
I have a 2009 LT with the 2.4L 6 speed transmission with just 75km on it.
I was driving in the city at just under 50 k/h ,as I lightly excelerated the engine revved up and then went hard into gear. I'm going to drive it for a few more days until I figure out what speed and circumstances this happens at , then I'll take it in to the dealer.
Anyone else with this problem?
I had something similar happen when the car had forgotten how to shift and they had to "quick learn" the computer... it wasn't a really hard thunk, but a fairly good one -- and the car jerked.
 
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