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Harsh Downshift

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Brucets11 New Member

Brucets11

Posted
Posted

I’m yet another that’s had this problem. Harsh or abrupt 2-1 down shift with ‘19 Silverado outfitted with 5.3 and 8 speed transmission. Bad enough that my wife looks at me and asks if the truck is safe to drive.  Dealer said they can’t duplicate it and everything seems ok.  But it happens almost all the time with me. 

 

Problem seems to be when transmission temp gets up to about 180 or above.  Abrupt shift happens when I reach about 6 or 7 mph when slowing. 

 

I tried the C4 learn yesterday and after one day I’ve not had the problem. Keeping my fingers crossed that this solved my problem. 

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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

dcarbs Enthusiast

dcarbs

Posted
Posted

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. 

  • Like 1
Bob2C Enthusiast

Bob2C

Posted
Posted

Has anyone ran their vehicle with the a/c off and noticed that the downshifting is not harsh? If not try it.. Mine is smooth when its off...

Brucets11 New Member

Brucets11

Posted
Posted

The shift problem with mine happened with and without the A/C on. It occurred in 2WD, 4WD, trailer mode, and sport. 

STX30MAC Enthusiast

STX30MAC

Posted
Posted

I have the 10speed with 6.2L and get the same hard downshift 2-1. Gives a shove forward right at 5mph. Doesn’t clunk but more a push forward. In Texas so we haven’t had a day a under 95. Since I got it in July. I will try it at night to see if it makes a difference.


Sent from my iPhone using Tapatalk

  • 10 months later...
MJJB New Member

MJJB

Posted
Posted (edited)

I bought a 2020 Trail boss a few months ago with 9 miles on it when I drove it off the lot. Around 300-400 miles I started to get hard down shifting while breaking and just cruising to a stop sign/light happens around 5 mph or so. I now have 5,000 miles and it still happen frequently. Just got it back from the dealer. They said they couldn’t get it to hard downshift. My guess is they didn’t drive it much. They couldn’t find anything wrong. They told me GM says that’s normal. I say BS. I’m going to bring it back again if it continues. My brother has a 2020 trail boss as well with no issues. 

Edited by MJJB
  • 5 months later...
bluemonstercali Enthusiast

bluemonstercali

Posted
Posted

Any update to the fellas that did the relearn. My sierra elevation started to do this around 500 miles. I am taking it in tomorrow to the dealer to have them look at it. I really like this truck and have done a few mods already. I hope they can fix this issue. Thanks for any updated response.

  • 3 weeks later...
Chevrolet1 Enthusiast

Chevrolet1

Posted
Posted

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 and forth between the low gears (e.g. 2, 3, 4). Secondly, when I come to a stop, it literally feels like someone gently rear-ended me. Called local dealer, they said first step is to change fluid, if that doesn't  solve it, next step is to replace parts (I believe beginning with the TC). Think I'll let them do the fluid change first, then maybe try the relearn.

  • Like 1
  • 2 months later...
VanDeWal New Member

VanDeWal

Posted
Posted

My 2019 has 40714 miles and still hard shifts to 1st but not consistently, waiting for it to break and leave me stranded one day, they know there’s a problem an act like we’re all stupid, may have to go back to a Ram

  • 1 month later...
Phantom 4D Enthusiast

Phantom 4D

Posted
Posted

Have the same issue with my 2019 Sierra SLT. Has a clunking noise coming to a stop. Back last year I had a bad problem with very hard downshift that shook the truck. I tried light braking, hard braking and coasting. This lasted most of the day. Next day, shifting was normal. Dealer said no codes, could not duplicate. Still have the clunk when stopping. Last service, mentioned it to service rep. Again got the "all the trucks do that" answer. 

dgstarr63 Enthusiast

dgstarr63

Posted
Posted

I have been driving,  servicing and restoring GM vehicles exclusively since 1964. This issue is the most closely guarded secret I have ever heard of. GM blamed it on the hydroscopic fluid from 2014-2019. Now that they have the improved fluid, the dealers claim they don't know what is causing. I will bet money that GM knows why some trucks do this, but are not willing to spend the money to repair them. GM, I know you are listening, so think about this: If you don't start standing behind your products the Ram trucks will continue to steal your sales. 

 

Very disappointed longtime customer.

Phantom 4D Enthusiast

Phantom 4D

Posted
Posted

dgstarr63- I am aware of the fluid issue. I had a 2017 Silverado that had shifting issues. Of course the techs would not admit anything. I found out thru a confidential source what was going on. Took the truck to the dealer, supposedly the tech was driving it when the fluid overheated. Went in to limp mode and he drove it back, eight miles, to the shop. Supposedly, again, the torque converter fried, trashed some other stuff. Took two weeks to fix. No converters available so GM had to pull one from the line. After all the repair steps, truck was ready to go. It drove fine for about a month then started with the hard shifting. Took it back, dealer said no issue. Had transmission had to relearn. After a few visits and some words, I traded it for the 2019 Sierra, which supposedly (that word again) had all the new stuff. By the way, friend of mine just traded his 2020 Sierra for a 2021 Ram. GM dealer couldn't or wouldn't fix the problems with his truck. Tranny, tailgate would open by itself, and electrical issues.  

mbfireboat Enthusiast

mbfireboat

Posted
Posted

I had this consistently for maybe two days around a year ago on my 2019 5.3, then it stopped. It only has happened once or twice since then. It was a very hard downshift at around 5mph when stopping. I think I had 1400 miles on it at the time.

 

Before I picked up my truck new from the dealer, they had performed a transmission flush per a TSB to a newer spec fluid. I don't know, maybe I had some moisture in the tranny. 

  • 1 year later...
Marco G New Member

Marco G

Posted
Posted

My 2022 Silverado has the same problem at 1200 Miles,toke it to the dealer they says it’s the transmission learning the need to re-program it after one week the problem came back but this time dealer sayid we can find the problem , toke it back home the problem became worst than before they have done check on it with NO LUCK, contacted GM without any help, I still have the problem goes and come back on daily basis, toke it for the 3rd time for the dealer to fix it again without luck, truck is in 10000 miles with the same problem , now sitting i. The dealer try to find solutions for the problem and still no luck . Any advice 

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