Those with 8 speed shudder problems?

[DTB]

I think my 16 Sierra 5.3/8 speed might be experiencing it. Seems to happen mostly around 45-50 under light throttle while cruising. It definitely has the rumble strip feel. It happens maybe two times for a second or two each and then it seems to go away. Also, the tachometer seems to flutter a lot, whether it is shuddering or not. Is this the symptoms that call for a torque converter or flush? I’m within 500 miles of the 3yr/36 so I want to hopefully get this resolved soon. I’m suppose to take it to the local Chevy dealer where my cousin works who is a transmission man. He is going to try to diagnose it although they said I really need to take it to the local GMC dealer (that I don’t like) for the warranty work? I figured GM was GM as far as that type of work went. 

[Bigrich]

I have same issue with me 2015 Denali with 6.2 & 8 speed tranny. I’d like to hear the outcome. I thought it may be a driveshaft vibrating? 

[Billy Smart]

My truck was doing the same thing. I was letting my son drive it and he really was not sure what was happening. I drove it to work one day and noticed it. I performed flush with fluid for mercedes-benz cars that have fe style fluid and it has been good for atleast 3,000 miles. I did not take to dealer since my truck was tuned. Fluid for me was free since I work for mercedes dealer. I figured if it didn't work, time for a circle-d stall.

[DTB]

Well I did some more testing today. It appears to be the worst going up a hill without it trying to down shift. It also seems to do a similar scenario if you can get it lugged down without it down shifting a gear on a slow acceleration. I wonder know if maybe it is the torque converter not unlocking/locking correctly. I managed to capture the scenario on video for my dealership visit. 

[SILVER SLED]

There is a bulletin for this from gm. Vaguely the fix is to drain and flush the trans fluid three times. 

[elcamino]

[DTB]

Did some more work experimenting. The newest form of that 5337 apparently excludes the 5.3 version with 8 speed. Anyway, I held it in m7 to disable AFM thinking it might help. It did seam to be less frequent but still did shudder going up hill. Immediately after I shifted into 8th on flat ground it shuddered as well. Tach flutter was the same regardless of AFM. 

[Brian Green]

My 2015 6.2/8 speed had this problem.  I complained about it to the dealership for 6 months.  They kept trying to tell me it was a tire problem and that it would only go away if I got away from AT tires.  Finally, on the 4th visit to the dealership, they flushed the transmission and replaced the torque converter.  Problem solved.  The tech said he didn't know what the actual problem was but could definitely tell something was "off" in the torque converter.  That was about 4 months ago, no issues since then.

[DTB]

Visited the dealership this morning. Went for a ride and as soon as he seen the tach fluctuating he knew it was a converter issue. They are going to do a 3 flush/fluid swap and see if it works. If not they will then try  a converter swap. They have had 4 different 8 speed issues this year ranging from a Camaro to a Colorado. 

[2017_LTZ]

I have a 5.3L with the 8 speed and I notice it the most during cold starts. My truck will shutter/surge up until it warms up. I have taken it to the my local dealer and they said it was "normal" and that the transmission was just relearning itself.... Sounds like a bunch of BS to me but if this problem continues or gets worse I will definitely go back and complain. 

[Glava2876]

2 hours ago, DTB said:

Visited the dealership this morning. Went for a ride and as soon as he seen the tach fluctuating he knew it was a converter issue. They are going to do a 3 flush/fluid swap and see if it works. If not they will then try  a converter swap. They have had 4 different 8 speed issues this year ranging from a Camaro to a Colorado. 

I can tell you from experience that the triple flush worked for my 2015 6.2 8A. It was done early on and now at 30k miles it has still been fine. I also have a 2015 Corvette that is a 7M, but on the Corvette site there have been the same issues with the 8M. Most times the triple flush works, but on a few they ended up with a new TC.

[DanielB]

On 4/9/2018 at 8:59 AM, Brian Green said:

My 2015 6.2/8 speed had this problem.  I complained about it to the dealership for 6 months.  They kept trying to tell me it was a tire problem and that it would only go away if I got away from AT tires.  Finally, on the 4th visit to the dealership, they flushed the transmission and replaced the torque converter.  Problem solved.  The tech said he didn't know what the actual problem was but could definitely tell something was "off" in the torque converter.  That was about 4 months ago, no issues since then.

I have the same truck and had my torque converter replaced also.  It was shuddering bad on the freeway, its been about 10 months ago, now i get the occasional slam into gear at low speeds.

[Fasttimes1977]

Same here. Developed a bad shudder and dealer replaced torque converter. No issues since

[samckitt]

Had my '18 5.3L/8 speed in at around 4k miles, they flushed it (or so they said), didnt resolve it, so they replaced torque converter, still didnt fix it, taking it back in this week for them to look at it again.

Edited September 4, 2018 by samckitt

[Bigmac]

2 hours ago, samckitt said:

Had my '18 5.3L/8 speed in at around 4k miles, they flushed it (or so they said), didnt resolve it, so they replaced torque converter, still didnt fix it, taking it back in this week for them to look at it again.

Good luck. Been there done that with my 17 8 speed. It’s inherit I believe with these trans and the  converters they use.  My understanding is 2019 8 speed has a different type of converter.  My 2018 does it also so I just lowered my expectations of a fix from GM.  Let me know what they figure out please.  Try and tow a trailer and watch the shudder magnify to the 10th power ??