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Harsh Downshift

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ACE01 New Member

ACE01

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Hey guys, I had the same problem in my 2021 Silverado 1500 with 8 spd trans.  The fix is have your dealer flush the transmission of the old fluid and replace with new spec fluid.  I don't have the exact fluid type on hand.  The dealers are aware of this.  This took care of all my crazy hardshift problems.   

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eddiek
eddiek

2019 duramax 1400 miles, when you down shift it feels like you get rear ended, shifting in general is just not smooth

dcarbs
dcarbs

Happens to me as well with the 6speed transmission. I just always thought the brakes were slipping but now it makes sense that it’s a hard downshift. 

Chevrolet1
Chevrolet1

Just purchased a 2019 LTZ 5.3 with 8 speed, only 5k miles on it. Two symptoms. One is that the trans doesn't shift smoothly. During slow or moderate acceleration, it seems to hunt for or shift back an

Phantom 4D Enthusiast

Phantom 4D

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Posted
9 hours ago, ACE01 said:

Hey guys, I had the same problem in my 2021 Silverado 1500 with 8 spd trans.  The fix is have your dealer flush the transmission of the old fluid and replace with new spec fluid.  I don't have the exact fluid type on hand.  The dealers are aware of this.  This took care of all my crazy hardshift problems.   

Dealer did that on my Sierra. No help. There is a class action suit against GM for these issues.

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