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2014 - 2018 5.3 6 speed downshift jerks

nluchau
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nluchau Enthusiast

nluchau

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My 2016 5.3 6 speed has me very frustrated to say the least.  I know I've brought this up before but I need to again. I am still getting the jerk downshifts when coasting/slowing to a stop.  I don't hear any clunk but it literally jerks at each downshift from 4-3, 3-2, 2-1.  If I am a little heavier on the throttle it may get better for a while but rarely does it feel like a normal downshift with a blip of the RPM's.  I currently have 27k miles

 

What's been done: I've complained about this day 1.  I love the truck but this just doesn't seem right and is a bear to drive in stop and go traffic.  

* On 1 occasion at 16k miles Dealer replaced valve body and TCM. Shift adapts were reset.  

* At 26k miles the shift adapts were reset again. 

 

Does anyone have advice or any remedy for this without voiding my warranty?  I've tried the range technology device, its great for disabling V4 but it doesn't resolve the downshift jerk.  I've tried disabling grade braking to no avail.  I've tried M5.  I've tried tow/haul. Where it seems slightly better at times I still get the jerk.  

 

I need fire power for the dealer before my bumper to bumper is up.  I have just under a year or 36k miles whichever of the two comes first.  Guessing miles.  

 

Thank you for listening!

 

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nluchau
nluchau

My 2016 5.3 6 speed has me very frustrated to say the least.  I know I've brought this up before but I need to again. I am still getting the jerk downshifts when coasting/slowing to a stop.  I don't h

nluchau
nluchau

No problem!  Seems to be a widespread issue with no resolution.  

btj_z71
btj_z71

Go for a custom tune like black bear.  They tune the ECM and TCM.  Will update the transmission tables too, makes a huge difference.   Another option is to check all the fluids in your drive

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ripcurlksm Enthusiast

ripcurlksm

Posted
Posted

I am at about 1,200 miles on a new 18 Silverado 5.3 and have subtly noticed this as well. Not through all the gears but a subtle jerk as I'm slowing down. Not too bad I figured its helping the brakes slow down a bit but glad you brought this up

nluchau Enthusiast

nluchau

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Posted
2 minutes ago, ripcurlksm said:

I am at about 1,200 miles on a new 18 Silverado 5.3 and have subtly noticed this as well. Not through all the gears but a subtle jerk as I'm slowing down. Not too bad I figured its helping the brakes slow down a bit but glad you brought this up

No problem!  Seems to be a widespread issue with no resolution.  

  • Like 1
btj_z71 Enthusiast

btj_z71

Posted
Posted
1 hour ago, nluchau said:

My 2016 5.3 6 speed has me very frustrated to say the least.  I know I've brought this up before but I need to again. I am still getting the jerk downshifts when coasting/slowing to a stop.  I don't hear any clunk but it literally jerks at each downshift from 4-3, 3-2, 2-1.  If I am a little heavier on the throttle it may get better for a while but rarely does it feel like a normal downshift with a blip of the RPM's.  I currently have 27k miles

 

What's been done: I've complained about this day 1.  I love the truck but this just doesn't seem right and is a bear to drive in stop and go traffic.  

* On 1 occasion at 16k miles Dealer replaced valve body and TCM. Shift adapts were reset.  

* At 26k miles the shift adapts were reset again. 

 

Does anyone have advice or any remedy for this without voiding my warranty?  I've tried the range technology device, its great for disabling V4 but it doesn't resolve the downshift jerk.  I've tried disabling grade braking to no avail.  I've tried M5.  I've tried tow/haul. Where it seems slightly better at times I still get the jerk.  

 

I need fire power for the dealer before my bumper to bumper is up.  I have just under a year or 36k miles whichever of the two comes first.  Guessing miles.  

 

Thank you for listening!

 

Go for a custom tune like black bear.  They tune the ECM and TCM.  Will update the transmission tables too, makes a huge difference.

 

Another option is to check all the fluids in your drive line.  Front and rear differentials, transfer case, transmission.  I replaced all mine with Amsoil and while no noticable MPG difference, it did drive better. 

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pd59 New Member

pd59

Posted
Posted

My 18 was fine, right up until the trans grenaded itself last month at 27k miles. Dealer rebuilt the transmission, and now I am having the same issues with downshifts. It’s annoying. 

Josh Powell Enthusiast

Josh Powell

Posted
Posted

Same thing on my truck. Not a jerk. But feels like someone taps the brake on downshifts when I start to coast into my 25mph town everyday. The most noticeable one I feel is at about 33 mph. Very annoying. Especially if I give it gas right as the truck downshifts. Kind of throws it out of whack.

ripcurlksm Enthusiast

ripcurlksm

Posted
Posted
53 minutes ago, pd59 said:

My 18 was fine, right up until the trans grenaded itself last month at 27k miles. Dealer rebuilt the transmission, and now I am having the same issues with downshifts. It’s annoying. 

Wow I'm 25k miles behind you, hope mine doesnt have that issue. Did the dealer give a reason why the transmission failed?

pd59 New Member

pd59

Posted
Posted (edited)
6 minutes ago, ripcurlksm said:

Wow I'm 25k miles behind you, hope mine doesnt have that issue. Did the dealer give a reason why the transmission failed?

I was told that the 4-6 gear planetary gears started coming apart, which then introduced metal shavings into the trans fluid pump. They replaced the torque converter, fluid pump, the broken planetaries, some clutches, and I believe the valve body. Thankfully it was covered under warranty. It was a mess. 

 

The dealer told me they re adjusted the shift points, so who knows. I need to bring it back over there, but I drive my truck a lot for work, so it’s a pain in the ass. 

Edited by pd59
Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted
10 minutes ago, Josh Powell said:

Same thing on my truck. Not a jerk. But feels like someone taps the brake on downshifts when I start to coast into my 25mph town everyday. The most noticeable one I feel is at about 33 mph. Very annoying. Especially if I give it gas right as the truck downshifts. Kind of throws it out of whack.

I'm not picking on you Josh. Your post was just a good example that included the jest of most others comments. What do you all believe a 'normal' downshift should feel like? I'm not talking to those who have actual mechanical issues...broken parts :lol:

 

A feeling like "a tap on the brakes"..."a tug"...especially with mild noise, clunk, is not an issue. Can you drive a manual? What does it feel like when you let the clutch out on the 3-2 shift? 

 

Go back to the days of the vacuum/governor operated automatics like the TH-350 or C4 or Torqueflite 727. People complained that they did not down shift to the 'proper' gear holding on to high until just before coming to rest or down shifting from 3 to 1 upon light acceleration under 10 mph feeling it abrupt and that it should already know the road speed and be "waiting' in the correct gear. It should know to go to a lower gear under high vacuum that signal a more rapid deceleration. Well they complicated it to no end and gave you what your were screaming for and now we are going to complain that it isn't Ferry Godmother pillow soft and totally unnoticeable? Tough crowd. Well they made a gear box that is truly seamless and always in the proper ratio. It's called a CVT and guess what. People complained that they could not feel the gears at all and that it felt 'weird' for a motor to remain at nearly a constant rpm regardless of speed. So they programed speeds into it and now we are complaining about that too. You seeing a pattern here? 

 

There is clearance between yokes and splines and gears so that parts can move at all and when you change load direction on something that isn't press fit tight there is a bit of mechanical noise as on piece of metal strikes the other and a sensation, which is REAL that there has been a change of speed between assemblies. Just like your inability to apply your brakes without feeling the sensation of deceleration. 

 

 

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nluchau Enthusiast

nluchau

Posted
  • Author
Posted
3 hours ago, Josh Powell said:

Same thing on my truck. Not a jerk. But feels like someone taps the brake on downshifts when I start to coast into my 25mph town everyday. The most noticeable one I feel is at about 33 mph. Very annoying. Especially if I give it gas right as the truck downshifts. Kind of throws it out of whack.

This is pretty much what I feel, the jerk feels like if you tap the brake.  And yeah you cant throttle it during a downshift or else it'll cause it to hissy fit.  

nluchau Enthusiast

nluchau

Posted
  • Author
Posted
2 hours ago, Grumpy Bear said:

I'm not picking on you Josh. Your post was just a good example that included the jest of most others comments. What do you all believe a 'normal' downshift should feel like? I'm not talking to those who have actual mechanical issues...broken parts :lol:

 

A feeling like "a tap on the brakes"..."a tug"...especially with mild noise, clunk, is not an issue. Can you drive a manual? What does it feel like when you let the clutch out on the 3-2 shift? 

 

Go back to the days of the vacuum/governor operated automatics like the TH-350 or C4 or Torqueflite 727. People complained that they did not down shift to the 'proper' gear holding on to high until just before coming to rest or down shifting from 3 to 1 upon light acceleration under 10 mph feeling it abrupt and that it should already know the road speed and be "waiting' in the correct gear. It should know to go to a lower gear under high vacuum that signal a more rapid deceleration. Well they complicated it to no end and gave you what your were screaming for and now we are going to complain that it isn't Ferry Godmother pillow soft and totally unnoticeable? Tough crowd. Well they made a gear box that is truly seamless and always in the proper ratio. It's called a CVT and guess what. People complained that they could not feel the gears at all and that it felt 'weird' for a motor to remain at nearly a constant rpm regardless of speed. So they programed speeds into it and now we are complaining about that too. You seeing a pattern here? 

 

There is clearance between yokes and splines and gears so that parts can move at all and when you change load direction on something that isn't press fit tight there is a bit of mechanical noise as on piece of metal strikes the other and a sensation, which is REAL that there has been a change of speed between assemblies. Just like your inability to apply your brakes without feeling the sensation of deceleration. 

 

 

Thanks for this piece of info Grumpy Bear.  I do find this helpful info, it really is, but heck this is 2018 we're talking about.  Technology is ever so advancing and one would think that a 5.3 with a 6L80 transmission would be tried and trued by now.  This isn't the first year of them.  

 

I truly feel it's all in the tune.  If GM would just address this I feel they could tweak the tune to drastically reduce or eliminate these issues. Give me 1 mile less per gallon tune that makes a truck drive like a truck.  

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ripcurlksm Enthusiast

ripcurlksm

Posted
Posted

good post grumpy, thanks for posting that. im just piling on since ive noticed the shift and have a new truck as a 2x silverado owner! ty!

Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted
1 hour ago, nluchau said:

Thanks for this piece of info Grumpy Bear.  I do find this helpful info, it really is, but heck this is 2018 we're talking about.  Technology is ever so advancing and one would think that a 5.3 with a 6L80 transmission would be tried and trued by now.  This isn't the first year of them.  

 

I truly feel it's all in the tune.  If GM would just address this I feel they could tweak the tune to drastically reduce or eliminate these issues. Give me 1 mile less per gallon tune that makes a truck drive like a truck.  

There are just under 8 BILLION people on this planet and each is unique. There is no program that can dynamically  manage that. There are millions of 6L80E's in service. For any given service year they are identical in programing. A bit different in build due only to manufacturing and assembly variances common to all things man made. The real differences lie in the users. There is no 'reboot' or 'reprogram' for that. This is why companies like Black Bear start with data collection directly retrieved from YOUR truck with YOU behind the wheel and go from there. GM, Ford nor Dodge can not do that in a cost effective manor. They do their best with adaptive learning algorithms. You're simply expecting to much. 

 

55 minutes ago, ripcurlksm said:

good post grumpy, thanks for posting that. im just piling on since ive noticed the shift and have a new truck as a 2x silverado owner! ty!

No worries. 

Josh Powell Enthusiast

Josh Powell

Posted
Posted

It may be normal and there may be a reason for it. All I know is that out of all my vehicles this is the first that I really feel the downshifts. I can live with it and I've even gotten used to it. Some days it still catches me off guard and feels unusual. Especially , like I said, when I'm just trying to go around 30-35 it's very noticeable.

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