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2020 Chevy gas harsh downshift

Nathan Leslie
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Nathan Leslie Enthusiast

Nathan Leslie

Posted
Posted

2020 Gas motor. Noticed that when coming to a stop there is a harsh downshift possibly from 2nd or 3rd to 1st. It is not violent but can definitely feel it. Anyone else having this?

TrucksAndDogs New Member

TrucksAndDogs

Posted
Posted

2020 GMC 2500 Diesel - have had for 4 weeks .... have experienced a harsh downshift a couple of times.  Certainly not frequent.  Trying to notice what conditions it occurs ... recall it happening once while on a slight forward incline.

mkeddie Enthusiast

mkeddie

Posted
Posted

Diesel is a different story cause of the 10 speed....but
Ive been told the trans need to learn how to shift like a break in

Sent from my Moto Z (2) using Tapatalk

SkidooSteve12 Enthusiast

SkidooSteve12

Posted
Posted
22 hours ago, Nathan Leslie said:

2020 Gas motor. Noticed that when coming to a stop there is a harsh downshift possibly from 2nd or 3rd to 1st. It is not violent but can definitely feel it. Anyone else having this?

In Tow/Haul mode or not? I get that when in Tow/Haul mode coming to a stop the engine breaking/transmission downshifting helps and it definitely downshifts and the RPM's jump up to 3000-4000 RPM's. But just normal driving I do not get that effect.

 

Double check that your Tow/Haul mode isn't turned on.

Nathan Leslie Enthusiast

Nathan Leslie

Posted
  • Author
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It is not in tow haul mode. I have done some towing with it as of recent but felt the bump when it was not in tow haul. Its sometimes more subtle than others. Its just something odd to me. maybe I am overreacting.........

SkidooSteve12 Enthusiast

SkidooSteve12

Posted
Posted

I haven't felt anything like that during normal driving. The only weird transmission shift that I've felt about 4-5 times is when I'm coasting and slowing down around 45 mph and then touch the gas pedal and it clunks when finding the right gear.

Nathan Leslie Enthusiast

Nathan Leslie

Posted
  • Author
Posted
1 hour ago, SkidooSteve12 said:

I haven't felt anything like that during normal driving. The only weird transmission shift that I've felt about 4-5 times is when I'm coasting and slowing down around 45 mph and then touch the gas pedal and it clunks when finding the right gear.

I have felt that one also. 

  • 4 months later...
Girthyhawg New Member

Girthyhawg

Posted
Posted
On 2/25/2020 at 12:26 PM, Nathan Leslie said:

It is not in tow haul mode. I have done some towing with it as of recent but felt the bump when it was not in tow haul. Its sometimes more subtle than others. Its just something odd to me. maybe I am overreacting.........

My truck is 2 Weeks old, this past weekend I took a 10hr road trip, everything was fine until I got off of interstate. 3 times in a row when I stopped for redlight or sign I felt same thing with a jerk.. like rear wheels were hitting a speed bump.  Came back home, truck drove normal with minor hard up shifting... when I got to dealer after another 10 hours to drop off, it happened again but not as severe. Dealer said the saw no codes, but would keep an extra day to see if they could simulate.

Stand By Enthusiast

Stand By

Posted
Posted

I feal it sometimes when turning a corner. Also the decel-accel lag described above. So far just chalked it up to normal mediocrity at a premium price.

  • 2 months later...
BC225 New Member

BC225

Posted
Posted

I have felt the same thing as u described. Just under 5000 kms on truck. 

InTrouble Enthusiast

InTrouble

Posted
Posted

Had the same thing happen a couple days ago from 2nd to 1st on a very slow deceleration. Trucks 3 weeks old about 1500 miles. Previous 3/4 ton I owned had the 6l with 6speed  I would get a similar reaction sometimes on slow decel. The new 6 speed has been beefed up slightly with a heavier spring pack and clutches according to some info from GM I ran into somewhere. So, that and the unit being new and still learning may be the issue, time will tell.

 

  • 2 weeks later...
William M. Campbell New Member

William M. Campbell

Posted
Posted

I had service done at 12,000 and told chevy dealer that my transmission was not working properly, around 40 when driving in town it shifts up and down a lot, hard clunk sometimes when shifting from reverse to forward.  The dealer said that they had installed the wrong fluid and that they would change it.  Has anyone else had this problem.  I have not had the fluid changed as of yet, I was wondering if that is just a ruse.

 

  • 2 weeks later...
Dunn Senior Enthusiast

Dunn

Posted
Posted

had both downshift coming to stop (3rd to 2nd gear i beleive) and the 45 mph one......but its very infrequent and i just chalk it up to being a new truck......i dont get alarmed too easily but if it becomes more frequent and or more violent i would check it out.......otherwise ill let it break in and see what happens  dtl......in tow haul mode have not had one issue......mine are all in normal mode

 

be nice if they had a mode right in middle between tow and normal....that would be a really sweet spot for this truck imo

 

mine is 6.6L gas

Rewopleahcim New Member

Rewopleahcim

Posted
Posted
On 2/24/2020 at 12:43 PM, Nathan Leslie said:

2020 Gas motor. Noticed that when coming to a stop there is a harsh downshift possibly from 2nd or 3rd to 1st. It is not violent but can definitely feel it. Anyone else having this?

I have experienced this many times.  Slow deceleration around 20km/h. Brought it to the dealer and big surprise, they couldn't duplicate it.  2020 6.6 Gas, started feeling this at 1000km mark, It has about 5000 kms now, still doing it.

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