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Posted
20 minutes ago, Patriot78 said:

Sorry should be specified, it's a 6 speed, I have a range afm  module so I can try and see if that makes a difference but I'm pretty sure when I was using it before it made no difference 

I'm using a DiabloSport tuner to disable mine. Fixed my shudder. Still down shifts a little hard though from 4-3 and 3-2.

Posted

I have a 2016 Silvarado LTZ Z71 4x4 with the 8 speed... About 13,500 miles on it and it's started to develop a "shudder" and it's been shifting harder. On cruise control it will shudder at around 1300 rpm. I've driven it in manual on new roads at 35 MPH and it also shudders. We're talking about vibration enough to shake the steering wheel. Almost the same effect as driving over bumps in the road. When driving it like as **** at higher RPMs the issue isn't as severe. Also when drifting, letting the vehicle decelerate, the issue goes away. 

Coming here I see there is a 772 page thread on the topic.... Any glaring conclusions? Talk about frustrating... 

 

Thanks for input,

JK29

Posted
1 hour ago, JK29 said:

I have a 2016 Silvarado LTZ Z71 4x4 with the 8 speed... About 13,500 miles on it and it's started to develop a "shudder" and it's been shifting harder. On cruise control it will shudder at around 1300 rpm. I've driven it in manual on new roads at 35 MPH and it also shudders. We're talking about vibration enough to shake the steering wheel. Almost the same effect as driving over bumps in the road. When driving it like as **** at higher RPMs the issue isn't as severe. Also when drifting, letting the vehicle decelerate, the issue goes away. 

Coming here I see there is a 772 page thread on the topic.... Any glaring conclusions? Talk about frustrating... 

 

Thanks for input,

JK29

I have the exact same truck and mileage as you and had mine in yesterday for a bunch of warranty work.  They did the 8 speed tranny tune upgrade and that has helped the shifting/searching issue so far but as soon as I pulled out of dealership I noticed my vibration exactly as you describe.  Watch your tach when you get the vibration and see if it jumps about 200.  I have a level kit and the tech said the vibration was due to tire issues.  I call BS and does not explain the tach flutter or the fact it goes away on deceleration.  My guess is torque converter just need dealer to see it that way. Good luck, I'll update when/if I get a fix.

Posted

Well I put my range and delete on while driving around today and it didn't do anything to stop the shudder at 25mph...i did however switch into manual  mode and shifted into 2nd gear (No shudder) 3rd gear(No shudder) 4th gear and up had the shudder 

Posted
9 hours ago, Buckem said:

I have the exact same truck and mileage as you and had mine in yesterday for a bunch of warranty work.  They did the 8 speed tranny tune upgrade and that has helped the shifting/searching issue so far but as soon as I pulled out of dealership I noticed my vibration exactly as you describe.  Watch your tach when you get the vibration and see if it jumps about 200.  I have a level kit and the tech said the vibration was due to tire issues.  I call BS and does not explain the tach flutter or the fact it goes away on deceleration.  My guess is torque converter just need dealer to see it that way. Good luck, I'll update when/if I get a fix.

Hey Buckem,

 

Mine has the RPM "flutter" as well every time the truck shudders. It swings about 150-200 RPM each shutter. My truck is 100% stock. It also goes away on deceleration.

Posted
On 10/17/2017 at 3:51 AM, lloydsmale said:

If my wife would have bought my truck she would never have said a word. Its shake plain and simple. May not be as severe as some have but NO vibration is expectable in a 45,000 dollar truck. Ive had chevs new since the early 70s and NONE of them had shake unless the tires were out of balance. Don't care how mild the shake is. Eventually its going to cause premature wear of some component in the truck. One of my main points is not everyone is mechanically inclined. Ive seen people drive cars and trucks with rod knocks that didn't even notice. Because your truck doesn't have it or you choose to buy into GMs bs that theres an acceptable limit to the vibration doesn't mean myself or someone else is going to stand for it. Theres something wrong here plain and simple. If there wasn't Gm wouldn't have gave me an extended warrantee. Only thing different between me and some others is I stood up to the dealership and said it was unacceptable at any level. There also wouldn't be a class action suit if it were only a handful of trucks effected. The problem is REAL. Stick your head in the sand or try to belittle others for complaining if you want. that's just what corporate GM and the major stock holders are hoping you will do.

lol... i never said there wasn't an issue. all i said was that if someone hadn't noticed it until you brought it up, it most likely wasn't what others are experiencing

Posted (edited)
20 hours ago, 8lugmafia said:

lol... i never said there wasn't an issue. all i said was that if someone hadn't noticed it until you brought it up, it most likely wasn't what others are experiencing

my point is that it is an issue. Be it a slight vibration or a cup falling out of the cup holder. there's no excuse for justifying ANY vibration in a truck that cost near 50k. I'm sure Gm is hoping ALOT of people think like you. ANY vibration that there all the time will cause premature wear of driveline, suspension and steering components. Maybe you will buy into there bs that some levels of vibration are within limits but not me. Ive owned to many chev trucks to know that this isn't the norm for them. Somethings wrong and Gm needs to address it. Let me ask you this. Gm in there great wisdom has determined that oil consumption isn't considered excessive unless your using more then a quart every 1000 miles. If your NEW  truck was using a quart every 1500 miles would you sit back and except and believe that's really normal??

Edited by lloydsmale
Posted
4 hours ago, lloydsmale said:

my point is that it is an issue. Be it a slight vibration or a cup falling out of the cup holder. there's no excuse for justifying ANY vibration in a truck that cost near 50k. I'm sure Gm is hoping ALOT of people think like you. ANY vibration that there all the time will cause premature wear of driveline, suspension and steering components. Maybe you will buy into there bs that some levels of vibration are within limits but not me. Ive owned to many chev trucks to know that this isn't the norm for them. Somethings wrong and Gm needs to address it. Let me ask you this. Gm in there great wisdom has determined that oil consumption isn't considered excessive unless your using more then a quart every 1000 miles. If your NEW  truck was using a quart every 1500 miles would you sit back and except and believe that's really normal??

And how exactly am I thinking. You clearly missed the point of what I was saying. Not once did I say there wasn't an issue that GM needs to take care of, nor did I say that small vibrations are acceptable. 

 

Looks like you got your issue resolved with wheels and tires, so I don't know why you're still bitter with me. Don't take your frustration with GM out on me bc I said your issue wasn't what others have with their transfer case or driveshaft or whatever it is. Considering your issue was resolved with wheels and tires, it only shows that what I was saying was correct. Take it easy. Glad you got your issue resolved

Posted
5 hours ago, lloydsmale said:

my point is that it is an issue. Be it a slight vibration or a cup falling out of the cup holder. there's no excuse for justifying ANY vibration in a truck that cost near 50k. I'm sure Gm is hoping ALOT of people think like you. ANY vibration that there all the time will cause premature wear of driveline, suspension and steering components. Maybe you will buy into there bs that some levels of vibration are within limits but not me. Ive owned to many chev trucks to know that this isn't the norm for them. Somethings wrong and Gm needs to address it. Let me ask you this. Gm in there great wisdom has determined that oil consumption isn't considered excessive unless your using more then a quart every 1000 miles. If your NEW  truck was using a quart every 1500 miles would you sit back and except and believe that's really normal??

Nope, wouldn't stand for a qt every 1,500 miles.  Would be asking for a resolution for sure.  However, I "think" the one qt/1,000 miles threshold is pretty much standard around the industry.

Posted

The first thing I would do is run first a dry compression check on all cylinders then repeat with a wet compression test.  And be sure to write down the results.  Look for excessive psi variation.

Posted

The first video, I'm idling (Slight vibration). The second is going down the interstate at 75 mph (Being agitated considerably).  I heard the TSB #16-NA-175 addresses this issue, but i have a V6, which isnt listed on the bulletin but its the same transmission. Hopefully the dealer still will cover doing this bulletin. Regardless it's not normal!

IMG_0506.MOV

IMG_0511.MOV

Posted
14 hours ago, Dmf10e said:

The first video, I'm idling (Slight vibration). The second is going down the interstate at 75 mph (Being agitated considerably).  I heard the TSB #16-NA-175 addresses this issue, but i have a V6, which isnt listed on the bulletin but its the same transmission. Hopefully the dealer still will cover doing this bulletin. Regardless it's not normal!

IMG_0506.MOV

IMG_0511.MOV

that's some serious vibration!! Much worse then mine. I sure wouldn't stand for that!

Posted
On 10/21/2017 at 11:05 AM, Snoringbear said:

Nope, wouldn't stand for a qt every 1,500 miles.  Would be asking for a resolution for sure.  However, I "think" the one qt/1,000 miles threshold is pretty much standard around the industry.

The oil consumption is caused by the AFM. Disabling it should stop oil consumption. If not, then there is a bigger problem.

Posted
7 hours ago, lylknutsak said:

The oil consumption is caused by the AFM. Disabling it should stop oil consumption. If not, then there is a bigger problem.

How/why would AFM cause excessive oil consumption?  Not being argumentative just wanting to learn.

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