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1st to 2nd rough shift

BigredGMC
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topgear1224 Enthusiast

topgear1224

Posted
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Thanks for this explanation.  Good to understand it's a software thing.
Ya in theory there won't be any long term effects from the rough shifts. Time will tell.

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jlong1984
jlong1984

Mine only has the harsh 1-2 shift when the transmission is cold and I go straight from reverse to drive. If I give it a few seconds before I shift from reverse to drive I don't get a harsh shift. 

vancealot29
vancealot29

I've tried that twice already with two different dealers, this is what I got back....   Hi, Vance. After speaking with your dealer, it has been found that the shift concern you are experienc

UGADawgs
UGADawgs

known issue for cold vehicles. let it warm up first or hold pedal down lightly until in 2nd after initial go.

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BigredGMC Enthusiast

BigredGMC

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13 minutes ago, topgear1224 said:

Ya in theory there won't be any long term effects from the rough shifts. Time will tell.

Sent from my SM-N975U using Tapatalk
 

I bought a 7 year warranty, I guess if it breaks down I should be ok for at least that time.

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IceOnly Enthusiast

IceOnly

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You would think after spending in excess of 50k on a new truck, you wouldn’t have tranny issues. My 15 Sierra shifted perfectly. No jerking or clunking. 

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BigredGMC Enthusiast

BigredGMC

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4 hours ago, IceOnly said:

You would think after spending in excess of 50k on a new truck, you wouldn’t have tranny issues. My 15 Sierra shifted perfectly. No jerking or clunking. 

Also making transmissions for over 100 years you would think they had it down pat. This is one of the issues when you sub it out to the lowest bidder. I just don't understand why ruin your reputation for a couple of bucks.  The paint chips so easily as well. I remember in the 90's GMC had a commercial having metal ball bearing dropped on the paint showing it's professional grade. Now I get chipped by a grain of sand. But this tranny in stop and go makes you nauseous. Slamming into 2nd every dam time.

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topgear1224 Enthusiast

topgear1224

Posted
Posted
You would think after spending in excess of 50k on a new truck, you wouldn’t have tranny issues. My 15 Sierra shifted perfectly. No jerking or clunking. 
Ironically their cheapest power plan is actually one of their very best performing.

The 4.3 has no torque limiting. It comes with 3.42 gears. When you move your foot the transmission downshift so there's no delay. It pops off manual downshifts better than the 8 speed or the 10 speed.

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  • 2 weeks later...
RubRsidedown New Member

RubRsidedown

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On 7/3/2020 at 3:23 PM, topgear1224 said:

Ironically their cheapest power plan is actually one of their very best performing.

The 4.3 has no torque limiting. It comes with 3.42 gears. When you move your foot the transmission downshift so there's no delay. It pops off manual downshifts better than the 8 speed or the 10 speed.

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Sad thing is, I got this High Country powered with the 6.2l to better haul our boat to the lake. 

I don't believe the 4.3l would enjoy that haul. 

20200712_164918.jpg

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topgear1224 Enthusiast

topgear1224

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Sad thing is, I got this High Country powered with the 6.2l to better haul our boat to the lake. 
I don't believe the 4.3l would enjoy that haul. 
20200712_164918.thumb.jpg.cba14557ee667641f2d53b25ed4829d0.jpg
Within its limits [emoji23].

Not even kidding I drove a custom 4.3 as a loaner and honestly thought it was a 5.3 with 3.42 (my truck had 5.3 and 3.23) until I checked the window sticker. It has a fat torque curve, and unlike the 5.3 doesn't get asthmatic as it approaches redline.

even out on the road I didn't really feel a difference until I pushed it over 70.

That stock 3.42 makes a huge difference. The G80 engages cleaner, just makes everything better.

The biggest thing for me though is instant response. A very predictable transmission. and I still love the fact that if I put it in an L and go all the way down to 1 as I slow down it will kick off perfectly matched downshifts with out me constantly slamming the - button. Wish the 8 speed and 10 speed would do that.

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Wiggums Senior Enthusiast

Wiggums

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Posted (edited)

My old man had the 460 V-8 in his F-250. I recall being so excited over the massive 245 hp and 380 lb-ft of torque. It was a majestic beast that could pull anything on God's green earth.

The current V-6 in Silverado produces 285 hp and slightly less torque at 305 lb-ft.

 

If people could pull anything on God's green earth with the 460, I'm sure the V-6 can handle a boat.

Edited by Wiggums
  • 8 months later...
Billchevy2019 New Member

Billchevy2019

Posted
Posted
On 7/2/2020 at 9:54 AM, newdude said:

Here is the TSB on the 1-2 shift.

 

I know this was posted some time ago. But this is interesting, just picked up a 2019 Z71 this past December. This has been my experience when I first start the truck and back it out the driveway, and then put the truck in drive. I basically control my throttle and try not giving the truck to much gas until this querk passes basically. The truck drives fine after this.

  • 9 months later...
Elrod New Member

Elrod

Posted
Posted

Bought a 2020 silverado 5.3 new.  8 miles on it.  Has done the 1-2 stall first of the day since new.  Also does the 2-1 clunk approaching a red light.  Had a 2016 that did better but would sometimes shudder like it wanted to cut off at or approaching a stop.  Drivers seat likes to clunk around in the 20 just like the 16 too.  

  • 2 months later...
Gary1996 New Member

Gary1996

Posted
Posted

I just bought a new 2022 Chevy Silverado Z71 and have to the issue of the harsh shift form 1st to 2nd gear every morning never fails you think gm would have a fix for it but I was told that is normal characteristics of this transmission 8-speed that's is B's 

16479108121783563380811996492492.jpg

16479108559445097624726043421338.jpg

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