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I just picked up my Acadia yesterday and I'm noticing that that shifts between 1-2 and maybe 2-3 and also when I need to pass seem slow and almost feels like the car falls on its face a slight moment before the power kicks in or the gears shift. I feel it and I audibly can slightly hear it "lag". Is this what the recall notice is for that I keep reading about on here?

It seems to be but my VIN# is 7J14...much later than the VIN# supposedly affected. Production date was approx between March 14th and March 26th.

If you had this recall fixed on your vehicle, PLEASE provide me with some details as to what you felt and/or experienced. MyGMLink does not yet recognize my VIN#, and the salesman seemed clueless that there had even been any recalls/TSBs for the Acadia yet. I take the car in this Thursday (April 5th) for the Paint and Interior protection and would like to have this taken care of while its there.

Any info would be appreciated. Thanks.
 

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My VIN is later also, and I agree there still appears to be a lag.
If I activate the manual shifting and do it myself, theres no lag, so its not that the engine doesnt have the umph.
I think the trany software just needs a tweak?

I think you can see what software version is in your car if you go to "tis2web.service.gm.com/tis2web" and type in your VIN#
 

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The Acadia has "adaptive shift controls" which is a means by which the transmission adapts its shifting based on various inputs including your driving style.  Since both of your cars are fresh off the lot, perhaps you should give it a few days to train itself and break-in.

I had the tranny recalibration done.  To me, the recalibration improved shifting at highway speed.  Before the recalibration, the tranny was lazy shifting down to 5th when starting up a grade.  As a result, I would keep pressing harder on the accelerator which would eventually command a downshift to 4th which resulted in whiplash for passengers.  Since the recalibration, the tranny selects and holds the appropriate gear much better and commands downshifts in a more timely manner.

My wife has commented that since the recalibration low speed rolling acceleration and acceleration from a stop are improved.
 

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darrink1 said:
I think you can see what software version is in your car if you go to "tis2web.service.gm.com/tis2web" and type in your VIN#
Wow, interesting link! I'd like to see others' results from this page to see if we all have the same upgrades.
1) Go to http://tis2web.service.gm.com/tis2web plug in your VIN and click "Get CAL ID"
2) Choose 'TCM Transmission Control Module' from the list, click NEXT
3) Highlight 'Transmission' from the list and cut-n-paste results in here...

Here are mine:

Part Number CVN Description
24243844 00005266 New calibration with RC4 improvements.
24243108 0000F922 New calibrations to address RC2 issues.
24242905 0000F365 New calibrations with drivability improvements.
24242883 0000A3C0 New calibration with cornering acceleration improvements.
24242268 0000D294 New calibration with drivability improvements.
24242070 0000FEAF New calibration to improve shift quality.
24242010 0000FB81 New calibration to improve 6-5 downshift and garage shift.
24241736 0000F592 New calibration to improve downshifts, up shifts, adapts and drivability.
12589213 00004220 Transmission
 

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Ya, its a nice site. They used to have a techbrief site for free, but they eventually switched it over to a password protected page. The techbrief was nice because it was what the service centers were seeing out in the field.
 

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My descriptions are all the same, CVN's different and part no's are all one digit lower numerically than ADMIN's.  I'm AWD.

On Edit: I agree with Web Raven below. There may be further room for improvement.
 

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Discussion Starter #7
Mine came back as this:

E4398: No calibration data found. I'm assuming one of two reasons...my VIN# is too new and not yet in the database, or my car is too new and the fix was made to it prior to delivery.

The more I am reading on this thread, the more I think it is probably just the adaptive trans. I won't bother the dealer with this unless it doesn't go away over time or gets worse.
 

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I had the upgrade done on my transmission before going on my Arkansas trip last weekend. When I first got the Acadia back, it seemed to be greatly improved. But after driving it 2,200 miles, the lag was still noticeable. Right around 40-45mph and again at 60mph. It acts like it just doesn't want to shift and it doesn't have any power unless you mash down on the gas pedal and force it. I think I'm going to have to bring it back in...
 

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Web Raven said:
I had the upgrade done on my transmission before going on my Arkansas trip last weekend. When I first got the Acadia back, it seemed to be greatly improved. But after driving it 2,200 miles, the lag was still noticeable. Right around 40-45mph and again at 60mph. It acts like it just doesn't want to shift and it doesn't have any power unless you mash down on the gas pedal and force it. I think I'm going to have to bring it back in...
Not that this is your problem, but you might want to check and make sure the floormat isn't on top of your gas pedal. This was an issue at one time and can give you the sensation of having to mash down the pedal to get it to shift.
 

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The floor mat is in place and not on the pedal.

It's definitely a feeling that the engine just isn't getting enough oomph to move the vehicle. It's almost like there's just no power until I press that pedal down a certain degree and then you feel like it "kicks" in and the engine revs loudly. It was like that the entire trip down to Arkansas and back. I let my father drive it, he's been a mechanic all his life, and without even mentioning the tranny thing to him, he asked if there was something wrong with it.
 

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The transmission cal in the Acadia was tuned to maximize fuel economy. What is actually happening is a quick shift from 1-2 and 2-3 with torque converter clutch lock. This is responsible for about 2mpg improvement in real world driving compared with not doing this. At 35 light throttle it shifts to 5th with torque converter lock and at 45 it shifts into 6th. The RC3 calibration upgrade smooths out the 1-2 and 2-3 shifts and helps a low speed 15-25 mph delay issue. RC4 makes other minor improvements as well as modifies a diagnostic routine. The trans constantly learns and adapts, so if your driving style changes, the trans will try to adapt. The trans team continues to make refinements and as improvements are developed they will be available with a simple "reflash".
 

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acadia7j100001 said:
The transmission cal in the Acadia was tuned to maximize fuel economy. What is actually happening is a quick shift from 1-2 and 2-3 with torque converter clutch lock. This is responsible for about 2mpg improvement in real world driving compared with not doing this. At 35 light throttle it shifts to 5th with torque converter lock and at 45 it shifts into 6th. The RC3 calibration upgrade smooths out the 1-2 and 2-3 shifts and helps a low speed 15-25 mph delay issue. RC4 makes other minor improvements as well as modifies a diagnostic routine. The trans constantly learns and adapts, so if your driving style changes, the trans will try to adapt. The trans team continues to make refinements and as improvements are developed they will be available with a simple "reflash".
Thanks for that info 001.

This explains a lot.
 

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24243843 0000590B New calibration with RC4 improvements.
24243107 000033D5 New calibrations to address RC2 issues.
24242904 0000F1EA New calibrations with drivability improvements.
24242882 0000A14F New calibration with cornering acceleration improvements.
24242267 00001863 New calibration with drivability improvements.
24242069 00008008 New calibration to improve shift quality.
24242009 00008526 New calibration to improve 6-5 downshift and garage shift.
24241735 000041B0 New calibration to improve downshifts, up shifts, adapts and drivability.
12589212 000040AF Transmission


Seems mine are the same as admin, some differences in the part number.
 

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acadia7j100001 said:
The transmission cal in the Acadia was tuned to maximize fuel economy
I wonder if that's a trend, i.e. maximize fuel economy at the detriment of more "sporty" shifting; I seem to remember reading the new Passat had a lag/hesitation issue, even after 1000 miles, which should have allowed plenty of time for the transmission to adapt. This was mostly solved by a software flash. Not sure if the reflash affected fuel economy, though.

Personally, I'd rather lose 1 or 2 mpg than have a laggy car. In fact, too much lag/hesitation could be a safety issue if you have to do an emergency maneuver (like the Corbomite Maneuver, ha ha...yes, I'm a geek).
 

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nxs138 said:
acadia7j100001 said:
The transmission cal in the Acadia was tuned to maximize fuel economy
I wonder if that's a trend, i.e. maximize fuel economy at the detriment of more "sporty" shifting; I seem to remember reading the new Passat had a lag/hesitation issue, even after 1000 miles, which should have allowed plenty of time for the transmission to adapt. This was mostly solved by a software flash. Not sure if the reflash affected fuel economy, though.

Personally, I'd rather lose 1 or 2 mpg than have a laggy car. In fact, too much lag/hesitation could be a safety issue if you have to do an emergency maneuver (like the Corbomite Maneuver, ha ha...yes, I'm a geek).
It's true. it's **** true.

Have a PAssat 4MO 3.6l V6. Noticed it on test drive and when I picked up the car. Iwas told by everyone that it will be fine when I hit 1000 miles. Hit 1000 and the lag was still there. The lag was there from a stand still not so noticable at highway speeds. There was also a bucking at stand still or low speeds. Well, my CEL went on at 1100 and the incompetent "PASSAT TEAM" that directed the service dept couldn't find the issue. Replaced fuel pump, coil packs, injector rail. Still the same. They replaced my vehicle with a new car. However, the hesitation was still there.

After I complained numerous times and called VWOA I was told a flash would be coming out. I got a pre-release flash by about 2 weeks and haven't had a problem since. Knocks on wood.

In the end, it was a spark plug that caused the problem. They were 100,000 mile plugs so they didn;t check or replace them. Serves them right for being so stupid that they took a beating on the value of the car.
 

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I was looking through the owners manual I downloaded and found on page 131 some info that might pertain to this issue:

If you need more power for passing, and you are: Going less than 35 mph (56 km/h), push your accelerator pedal about halfway down.
Going about 35 mph (56 km/h) or more, push the accelerator all the way down.

(needless formating added for emphasis)
Since none of the cars I've driven have worked quite like this I can imagine that it would seem like a problem.


I haven't even had a chance to test drive one of these vehicles yet though so maybe I don't fully comprehend.
 

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I think if it's still brand new, that the lag is probably just that it hasn't learned your driving. I, too, complained about this after I first got mine, but with about 750 miles on it, I definitely notice a difference in the way that it drives. It's MUCH better. I guess it does just need to learn your driving style.
 

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Over 4,100 miles and I still have that one spot right around 45mph, but it's not consistent. So either I'm learning how to drive around it, or it's adapting to my driving. Either way, I can definitely live with it.
 

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I don't seem to have the lag. I really paid attention to it coming home. I don't know if it's because I always drive manuals, but I have a tendency to take my foot off the accelerator right before the shift. Is this a bad thing to do? It helps on the pick up, but I don't really know much about automatics and I don't want to do something weird to my car.
 

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mckcab...no need to take your foot off before shifts. Engine and trans "talk" to each other and engine torque and shift "pressures" are adjusted. This is the "learning" that all are talking about. As mentioned before, the transmission calibration is really trying to maximize fuel economy. It does this by trying to keep the engine rpm as low as possible. If you drive with a "heavy" foot, you'll probably not notice too much difference from a typical automatic, since the transmission will "skip" the fuel economy shifting. You'll also get lower gas mileage. If you drive with a "light" foot, you'll notice that at low speeds 20, 25 mph that the shifts into 2nd and 3rd will occur quickly. This can feel like a "hesitation" but if you watch the tach, you'll see you're really at a very low rpm...I'd call it on the "edge" of bogging like you'd see in a manual transmission at those low speeds. The Acadia is really trying to help you adjust your driving mode to get better mileage.
web raven, the spot you feel around 45 is the same thing happening when the Acadia shifts into 6th. You'll notice that the engine is turning only about 1200rpm at that speed...again...trying to improve fuel economy.
For all thread readers, if you want more control over your transmission (at the expense of fuel economy), pull the selector back into "L" and use the +/- button on the left side of the shift knob to shift however you'd like. The trans will try to respond to your wishes, unless you're wishing it to do something that would hurt it. If there's more interest on the "L" mode, I can cover it later.
 
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