8 speed transmission TSB flush

[askibum02]

My ‘17 Silverado 1500 LTZ with the 8 speed has been hesitating and shifting hard every morning when it’s cold for about the past 6 months.  Is that something that would be covered by the TSB for the flush?  I’m at just over 45k miles and I’m due for it anyway.  If I don’t have to pay for it that would be great.

[smileyman57]

I had those same symptoms and they seem to be much improved after the fluid exchange per the bulletin.  

 

I did not complain about that this time though.  I had a different torque converter shudder than what I see typically on this forum.  Mine was under heavy load like entrance ramp acceleration and then much more noticeable when pulling the trailer, mostly up to 4th gear and then ok after that and cruising.  I never felt any vibrations when cruising and then slightly increasing speed like many have described. 

 

Smooth as glass now.  It seems to have helped the harsh 1-2, 2-3 upshifts and the harsh 2-1 downshifts as well.

 

2017 Sierra 6.2L with 32k on it.

 

Edited June 5, 2019 by smileyman57

[Black02Silverado]

On ‎5‎/‎9‎/‎2019 at 10:46 AM, askibum02 said:

My ‘17 Silverado 1500 LTZ with the 8 speed has been hesitating and shifting hard every morning when it’s cold for about the past 6 months.  Is that something that would be covered by the TSB for the flush?  I’m at just over 45k miles and I’m due for it anyway.  If I don’t have to pay for it that would be great.

Call your dealer and find out.  Seeing the issues GM is having and going through the trouble of reformulating the fluid.  I would think it would be covered.  

[ftwhite]

My dealer wouldn't. 2018 LTZ. Pointed me to another TSB that said hard shift from 1-2 in cold state is normal operation. I can find the TSB number if you'd like.

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[duckcommander]

I would like that tsb please 

[YukonXL04]

On 6/6/2019 at 12:50 AM, ftwhite said:

My dealer wouldn't. 2018 LTZ. Pointed me to another TSB that said hard shift from 1-2 in cold state is normal operation. I can find the TSB number if you'd like.

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My dealer told me the same thing. How is a solid 2-3 second delay between 1st and 2nd shift "normal operation"?

 

But mine only does it maybe 3 times a week, so I don't really want them screwing with it and ending up with any of the numerous other issues...

[ftwhite]

I would like that tsb please 

Doc ID: 4605342


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[duckcommander]

Thanks

[Paintor]

On 6/6/2019 at 1:50 AM, ftwhite said:

My dealer wouldn't. 2018 LTZ. Pointed me to another TSB that said hard shift from 1-2 in cold state is normal operation. I can find the TSB number if you'd like.

Sent from my SM-G960U using Tapatalk
 

Here it is:

 

https://www.classaction.org/media/francis-et-al-v-general-motors-llc.pdf