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so there is another update afterall..
it should benefit those who are having problems on an incline..i'm good with mine.
 

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Discussion Starter · #3 ·
I've got a couple of long uphill climbs on my commute and do notice the frequent 5th/6th cycling, so I'm anxious to see some of the feedback from those that get the update. Sounds like it might be a challenge to get the dealers to find it in the TSBs, at least initially.
 

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This one was not easy to find:

#PIP4378: Busy Shift With Cruise - keywords 07 08 5-6 6-5 6t70 6t75 busy control downshift ecm mh2 mh4 mh6 my9 r1 r2 r3 seq shift tcm upshift v1 v2 v3 - (Mar 28, 2008)

Subject: Busy Shift with Cruise

Models: 2007-2008 Saturn Outlook
2007-2008 GMC Acaidia
2008 Buick Enclave

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The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Customer may comment that transmission shifts are busy at highway speeds when cruise control is engaged. Shifts 6-5, 5-6

Recommendation/Instructions:
Transmission Calibration sensitivity to throttle position changes.

Reprogram the TCM and ECM using the SEQ selection from TIS2WEB, SPS Pass-Thru method release 3.5 (2008) or greater.

Perform the fast learn procedure to learn transmission adaptives. Important: If fast learn does not complete, a no drive or reverse condition can occur, see PIP4203

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
 

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Discussion Starter · #5 ·
GeoHawk said:
This one was not easy to find:

#PIP4378: Busy Shift With Cruise - keywords 07 08 5-6 6-5 6t70 6t75 busy control downshift ecm mh2 mh4 mh6 my9 r1 r2 r3 seq shift tcm upshift v1 v2 v3 - (Mar 28, 2008)

Subject: Busy Shift with Cruise

Models: 2007-2008 Saturn Outlook
2007-2008 GMC Acaidia
2008 Buick Enclave

-------------------------------------------------------------------------------

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Customer may comment that transmission shifts are busy at highway speeds when cruise control is engaged. Shifts 6-5, 5-6

Recommendation/Instructions:
Transmission Calibration sensitivity to throttle position changes.

Reprogram the TCM and ECM using the SEQ selection from TIS2WEB, SPS Pass-Thru method release 3.5 (2008) or greater.

Perform the fast learn procedure to learn transmission adaptives. Important: If fast learn does not complete, a no drive or reverse condition can occur, see PIP4203

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
Thanks for finding this. So is this considered a TSB or does it fall under some other repair category?
 

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I think you are right that it is not global. I actually think all the tranny updates have not been global. If you are happy with the way it performs, I would suggest not getting this done. It could actually cause other issues that you might not like.
 

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Discussion Starter · #8 ·
This might be a dumb question, but can they 'undo' an update like this if it does indeed cause some other undesirable issues? The 5th/6th cycling is an issue for me, but not so much that I can't for a while to see what kind of feedback give after getting the update.
 

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Jake's right, it's not a TSB. It is another one of those preliminary information documents. If you go into the dealer and complain about transmission shiftyness/busyness (are those even words? :p ) the tech can pull up this doc. It is not something the service dept is going to do unless you complain about it.

Keeferb, I don't know if these updates can be undone. Just off the top of my head I would say yes - they could just upload the original programming again. But I don't know if this is easier said than done.
 

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I just got back from a trip to Florida and back (Indiana) and noticed the 'busyness' of the shifts between 5th and 6th. Since I have the trailering package, I selected the trailer button, and the transmission held 5th longer, and the shifts weren't as often. I do have the delay response that was really annoying during that trip. It almost caused us to be rear-ended a couple of times. It is more pronounced when you are coasting behind slower traffic, then want to move over, accelerate to pass. You hit the pedal, but nothing happens for a few seconds (feels like a minute when cars are barreling down on you). It then down shifts too far, and you are "taching" close to redline.

I had some other work done at the stealership today, and they stated the the re-flash didn't complete from the last time, so they re-did it. We'll see what happens. I hope they didn't download the new flash for the busy shifting.

Bill
 

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The other day I was towing my boat after its annual service and while pulling up a long incline the transmission suddenly shifted down to second gear and the tach shot up to nearly 7000 RPM. I was doing around 55 MPH and did not have the accelerator pedal pressed very far to the floor. It scared the heck out of me since I have towed up this hill many times and have never had this happen. The strange thing was that it would not shift out of second gear until I pulled to the right shoulder and nearly came to a stop. Even after Itook my foot off of the accelerator pedal. The rest of the trip I had no problems and it towed as usual. I have the trailering package and it was in the tow mode. Anybody else experience this problem?

My 5k service is coming up next month so I will be sure to address it with the service advisor.
 

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exprezchef - That does not sound good. If it happens again, try shifting into L and manually moving the max gear up and down. It might be a software problem and this might make it go away. Or perhaps you already tried this. Good luck!!!
 
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