Transmission is continuallly downshifting even.

Tiny
NADINEJOHNSON
  • 2007 GMC ACADIA
  • 39,825 MILES

Transmission is continuallly downshifting even on small grades and mileage has been cut because of this. Have been advised tcm/valve assembly is bad? Could this be the case after this few miles?

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Wednesday, January 30th, 2013 AT 5:42 PM

9 Replies

Tiny
GMTECH
  • EXPERT
  • 552 POSTS

After checking with my General motors bulletins there is quite a few issues with your vehicle when it comes to transmissions. Is your engine light on? Have you had it checked for codes. Do you have any leaks?

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Wednesday, January 30th, 2013 AT 6:39 PM
Tiny
NADINEJOHNSON
  • MEMBER

No leaks, no engine light on, just response from the GM techs when I asked about a software upgrade for the transmission that after checking, it was the tcm/valve assembly going bad.

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Wednesday, January 30th, 2013 AT 8:31 PM
Tiny
GMTECH
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You wouldn't happen to have an insurance monitoring device plugged in to your diagnostic connector under the dash would you?

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Wednesday, January 30th, 2013 AT 8:36 PM
Tiny
NADINEJOHNSON
  • MEMBER

No, nothing out of the ordinary except that the transmission wants to downshift over a little anthill and the rpm's go to 3000 so the gas mileage is shot.

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Wednesday, January 30th, 2013 AT 8:40 PM
Tiny
GMTECH
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  • 552 POSTS

Acadias do have finicky transmissions but I think you are at the point where it should be scanned and checked out at a tranny shop. There are too many variables to really know unless it is opened up

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Wednesday, January 30th, 2013 AT 8:46 PM
Tiny
NADINEJOHNSON
  • MEMBER

Okay, thanks. I am going to drop it at the dealer's this afternoon and let them have a closer look. Hopefully the news will be good or at least bearable.

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Wednesday, January 30th, 2013 AT 8:50 PM
Tiny
GMTECH
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I am guessing your are out of warranty but possible drivetrain warranty. If you have been good about maintenance don't hesistate to call Gm customer service to see if they will help you out if you don't get anywhere at the dealer

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Wednesday, January 30th, 2013 AT 9:04 PM
Tiny
NADINEJOHNSON
  • MEMBER

GM is going to cover 2/3 of the cost of repairs as the vehicle went out of warranty in May of 2012. Bought new and never did like the transmission.

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Wednesday, January 30th, 2013 AT 9:31 PM
Tiny
GMTECH
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That is awesome

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Wednesday, January 30th, 2013 AT 9:32 PM

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