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A number of Outlook owners have reported experiencing an acceleration lag related to the transmission. A member on the Saturnalia site posted the following:

You are correct, this is a software calibration issue. Engineering has released a new running calibration change to address performance issues. The new calibration improvement is significant enough that Lambda Platform has requested the change be pushed to the dealerships so that vehicles may be reflashed prior to sale or viewing.

I'll try to find out when this new calibration should be availble at the dealership.
The relevant thread is here: http://www.saturnfans.com/forums/showthread.php?t=94866#post1006703

Has anyone heard anything about this with respect to the Acadia?

Kelly
 

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I've seen posts about it on another site that shall remain nameless ;) However, I find it very interesting with all the activity on this site that I haven't seen any actual Acadia owners mention it. Could it be that it was fixed in their vehicles prior to delivery?
 

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I don't think its gone unnoticed...I truly think its a matter a preference. As the core of the issue is when the transmission downshifts - if you put the foot to the floor the shift occurs very quickly w/out hesitation. If you "half-way", the transmission either downshifts or remains in gear with a torque converter unlock.

It seems to me that GM was very conservative with the shift pattern to preserve MPG...I've heard the vehicle is adaptive (not sure if this is really the case), but frankly once you drive it for a time you'll learn how to make it react the way you want.

To me, it has plenty of torque on the bottom end to get it up to speed w/out a shift, and even when it does, it responds authoritatively (the driving experience is really not that much different to me than my Grand Prix GTP - it holds the higher gear unless you really want the umph, which requires petal down.).

So, again, I think its preference - don't get me wrong - I love wringing ot my wife's Solara out (3.0l VVT), but my 1999 Grand Prix gets better gas mileage despite being 600 lbs heavier and having a much bigger engine - the transmission and its programming really makes a difference in the experience, which is really relative to what you've driven before.
 

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I dont know, but I have a issue with 4th gear.

I leave a stop and with light pressure on the pedal it shifts fine through 1st 2nd 3rd and then the dreaded 4th gear. It's almost like you let off the pedel it just stops accelerating unless you mash it down much farther sometimes kicking back down to 3rd.
A little agrevating to try to drive without a heavy foot and hit this dead spot.



Maybe it's just mine or programned that way for mileage.
 

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There are presently two transmission performance related PI documents out. Both were released in the last few days and both involve an updated calibration for the TCM. "Preliminary Information" document ID # 1908397 - Performance Issue During Low Speed Acceleration After A Coast Down - keywords hesitation #PIP4058 - (02/20/2007) and Document ID# 1906376 - Transmission Performance Issues With DTCs - keywords dtc P0776 P0777 P0796 P0797 P0843 P0873 P0878 P0990 P2714 P2723 P2724 #PIP4050 - (02/15/2007)
 

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yeah. I definately feel the Acadia isn't real fond of downshifting. I do remember reading this in the early reviews. According to one of the reviews, there is apparently the same issue reported on the Fords that have been out longer than the Lambdas and the answer was "we're working on improving that".

Hey JimDandy. From your post it sounds like the dealers may already have the OK to make this change? You think this will be something they can do soon? Obviously those of us who already have our cars will need to see the dealer soon for that Airbag recall so it would be nice if they could make this update at the same time.
 

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Both TCM recalibrations were available for dealer download on 2-19-07. The airbag programming fix was available for download 2-18-07.

There is also a fix out for inaccurate fuel guage readings in cold climates. It involves installing a new fuel level sender in the tank.

Another fix is available for: Air Inlet Panel to Windshield Gap-Water Intrusion into Engine Compartment. Look at the very base of your windshield on the exterior about in the middle. The air inlet panel is slightly raised at the windshield junction creating the "gap".

I'm in a cold climate but haven't noticed the fuel guage problem.....yet. I do have the "gap". Ah,,,,,the joys of being an early adopter. Only had the Acadia a couple of weeks. Love it.
 

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Here's a piece from Edmunds.com talking about the tranny.

Capable engine — confused transmission
That image starts with a torquey, variable-valve 3.6-liter V6 engine that's standard across its two Acadia trim levels — SLE and SLT. Power is a healthy 275 horsepower and 251 pound-feet of torque, with that torque peak occurring at a readily accessible 3,200 rpm. It doesn't exactly make the 4,900-pound vehicle feel sprightly, and high-rpm refinement isn't quite class-leading, but this engine does motivate the Acadia with authority — assuming the transmission cooperates.

Unfortunately, as with the Saturn Outlook we drove recently, the Acadia's 6T70 six-speed automatic can be slow to downshift. This is the same automatic used in Ford's Edge (as part of a Ford-GM joint development project), and in each of these applications we wanted more responsive downshifts, as well as more gear lever positions to choose from. (You only get "D" and "L.") The conservative programming of the transmission likely bumps fuel mileage on the EPA's test loop, and the Acadia's rather impressive 17/24 mileage rating in all-wheel-drive form (18/26 in front-wheel drive) suggests the tranny's programming is effective for that purpose.



I would be interested to hear from those lucky folks who actually HAVE an Acadia to let the rest of us know if using the manual shift in 4th gear helps keep the vehicle from really dropping off in power? Sample holding 3rd gear a little longer before shifting to 4th would let the engine build more torque/HP to keep it accelerating...just a thought.

Thanks
 

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Only had mine a couple of weeks and it's the wife's car so have limited seat time.  I haven't really noticed the 4th gear issue alluded to but, live at high elevation in the mountains with many hills both rolling and steep.  I have been disappointed when needing to kick er down at highway speed that downshifting to 5th doesn't give me what I need to maintain speed on hills.  Did play with the tap shifting yesterday and will be using that feature frequently.  Makes it easy to get the revs you need to respond to conditions.  Moving the selector to "L" at highway speed commands a shift to 4th.  You can then tap up or down from there (I'm sure the tranny is smart enough not to permit over reving).  Manually selecting a gear means that the tranny will not shift into a taller gear than the gear chosen.  Otherwise, the tranny operates normally.  ie If you pull away from a stop sign with 3rd manually selected the tranny will shift from 1st to 2nd to 3rd and hold in third at the appropriate speed.

On another note, got to try out the AWD yesterday on a very slick I-80 in Wyoming.  Confidence inspiring.  No slipping, felt very stable.
 

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I too feel that surge in the tranny. It just feels like (around 40 -45) it wants you to put your foot through the floor to keep it going and when you do it goes (a hesitation in 4th gear)...only problem is that you will soon be doing 80. If you keep stepping on it- it will keep on going strong. Love the truck, but it does need some tweeking!!! Does anyone have anything we can print off to give to the dealer....I am sure they will be oblivious ( or act that way) of any problems. Thanks Gman
 

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Does anyone know what the chances are that GM will incorporate these updates into the vehicles currently in production so that they don't have to be changed later, or will it upset production enough that they will continue "as is" and force the new buyers to try to get the dealerships to make the updates? ESPECIALLY the computer upgrades for the transmission.

thanks
 

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I believe they get the programming updates on the assembly line at least as soon as they get the updates out to the dealers. For the critical stuff (airbags) they definately do (liability). Often times the messages announcing fixes for various issues will contain the VIN number spread for affected vehicles. This implies they fixed the issue on the line at a certain VIN number. Sometimes the messages will include a build date after which the issue was corrected.
 

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Minority report: I've been very pleased with the performance, including transmission shifting. No hesitation or lag and it shifts smoothly through all gears. [I'm in Florida, so hills aren't an issue. In fact, hills aren't at all.] Highway response is excellent - I pulled out to pass at about 52 mph in a short passing zone and, having read about the supposed hesitation, kicked her good to get going. Whoooowee! Instant downshift, instant 7000 RPMs (with very little noise) and I literally rocketed around that slow moving car! Had to back off in a hurry!

I came from a relatively puny 2.5L V6 in a Chevy Tracker (Suzuki Grand Vitara clone), so perhaps my expectations for performance are somewhat less than many of you enthusiasts here. Still, I've not been accused of having a light foot (as my wife frequently reminds me!).
 

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Given the recall information on this site, was able to get the dealer to do the computer flash one that covers the airbags and the transmission before I picked it up Saturday. No feedback on effectiveness yet, but saved run back to dealership! ;D
 

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Seems to me that people who get the update notice an improvement. If you haven't done so already, maybe you should ask the dealer about it the next time you're there. Can't say that I've seen any of the people from this thread on the one where they have gotten the update performed. The feedback there seems to be pretty good.
 

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Source: http://blogs.cars.com/kickingtires/2007/03/outlook_engine_.html

HTML:

			<h3 class="entry-header">Saturn Tackles Outlook Engine Lag</h3>
	
	<div class="entry-content">
		<div class="entry-body">

Saturn says it is now addressing a problem with transmission hesitation in its new Outlook SUV. As reported in our Dec. 5 [url="http://research.cars.com/go/crp/research.jsp?&revid=50624&makeid=43&modelid=8378&year=2007&revlogtype=20&section=reviews"]full review[/url], lag in the six-speed automatic was the only major strike against what is otherwise an impressive new eight-seat crossover. We found in our test Outlook that there was a slow reaction when the accelerator was depressed, and that raised safety concerns. As hoped, Saturn has developed a new calibration for the transmission-control module, which the company has begun to use in manufacturing new Outlooks. Though there is no recall at this time, any owner who is dissatisfied with the transmission performance can have it recalibrated at the dealership.</p>


We’re attempting to get our hands on a revised Outlook as soon as possible and will report back if it gets a clean bill of health.</p>
 

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I've only put about 70 miles on mine so far and haven't gotten it out onto the freeway yet, but I've had it up to 60mph and haven't noticed anything wrong with the way it shifts.

I do notice that from a complete stop, unless you jam on the gas pedal (which I like to avoid), it seems a little slower to take off. But I chalked that up to the fact that I'm used to driving a Saturn Vue (had 2 in the past 5 years) and the Vue is a smaller vehicle than the Acadia. My Vue was quite quick at everything. It seems to me it takes more time to bring my Acadia to a complete stop as well. Again, I figure it just weighs more than what I'm used to. I'm sure that I'll adjust. :)
 

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JimDandy said:
There are presently two transmission performance related PI documents out. Both were released in the last few days and both involve an updated calibration for the TCM. "Preliminary Information" document ID # 1908397 - Performance Issue During Low Speed Acceleration After A Coast Down - keywords hesitation #PIP4058 - (02/20/2007) and Document ID# 1906376 - Transmission Performance Issues With DTCs - keywords dtc P0776 P0777 P0796 P0797 P0843 P0873 P0878 P0990 P2714 P2723 P2724 #PIP4050 - (02/15/2007)
Now that is interesting - I have a Saturn Outlook and took in today. They applied...

Trans feels sluggish
"cause codes"
Document ID 1908427 and recalibrated TCM

Opcode K5364

I wonder if there is a difference between the GMC and Saturn????
 

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webhair said:
JimDandy said:
There are presently two transmission performance related PI documents out. Both were released in the last few days and both involve an updated calibration for the TCM. "Preliminary Information" document ID # 1908397 - Performance Issue During Low Speed Acceleration After A Coast Down - keywords hesitation #PIP4058 - (02/20/2007) and Document ID# 1906376 - Transmission Performance Issues With DTCs - keywords dtc P0776 P0777 P0796 P0797 P0843 P0873 P0878 P0990 P2714 P2723 P2724 #PIP4050 - (02/15/2007)
Now that is interesting - I have a Saturn Outlook and took in today. They applied...

Trans feels sluggish
"cause codes"
Document ID 1908427 and recalibrated TCM

Opcode K5364

I wonder if there is a difference between the GMC and Saturn????
There is no difference between the GMC and the Saturn. You might want to verify with the dealer that you got the latest update for the trans.
 
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