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Posted
On 4/6/2018 at 12:38 PM, amxguy1970 said:

The consensus is the same in all the other threads you searched, nothing has changed each situation and each dealer response is unique.

 

Not sure what to tell you but try another dealer? What makes it infamous? Is it like the infamous tire shake that less than probably 1% of the trucks exhibit?

 

Funny you bring up price, you didn't pay enough. If you had purchased the $60k truck it would be clunk free...

 

Tyler

No clue about the transmission but your 1% of trucks with the "tire shake" is flat out horsepoop.  I'm personally 2 for 2 on it myself with a 14 SLT crew and 16 SLE double.  Funny thing is, I can reproduce the problem every day of the week.  My console shakes so bad I have to wedge my leg against it but hey, nothing to see here....

  • Like 1
Posted

I had 2 different programming update that solved or at least made the trans better by quite a bit. It's not perfect by any means but I enjoy driving the truck again.
The tire shake happens in much, much more than 1%. Every 2014 + that I've driven except one had the shake. Even owners that don't seem to notice it, I've felt it.
I feel your pain about the price paid and even at half that price the vehicle shouldn't have any engineering issues that aren't worked out or even solved... especially years later!
Maybe see if your dealer will do the updates? (They should!)

Sent from my SM-N950U using Tapatalk

Posted

Do you experience tachometer flutter? Mine bounced up and down and it’s the torque converter lockup causing the issue. 

Posted (edited)

Had the clunk issue and spoke with my service advisor.  He said it was common but went away after about 15,000 miles.  :fume:  It turns out that at 11,000 miles after I changed from P-metric to LT radials, the clunk disappeared.  I'm now at 18,000 miles and the shifting is as smooth as silk.  Go figure.

 

Had the tachometer flutter after going down an 8% grade pulling a travel trailer holding 20 mph in manual mode.  It fluttered between 2nd and 3rd when I shifted back into automatic mode.  I put it back in manual after on the straight road, shifted manually up to 8th and no further problems.  Spoke with my service advisor and he made a note of it in my service file.

Edited by elchilero53
Posted

Gm just put a new torque converter in my 2015 denali 6.2 with 80k on it when then clunk became a bad shudder. Not sure if they did anything else while they had it but no clunk since getting it back

  • 3 months later...
Posted (edited)

We have/had this problem (clunking and hard down shifting) in a 2017 Chevy Silverado 8 speed and just won a lemon law case.  Don’t give up!! 

Edited by Boomer1986
Posted

See my previous response above.  I am at 24000 miles and the clunk in the shift from 2nd to 1st on acceleration around a curve is pretty much gone.  Personally, I think it was the change from P metric radials to LT tires that made the difference but I could be wrong.  I also towed our trailer 3900 miles in April and the truck ran just fine and shifted perfectly.  Is this a break in issue?  Anyway, I'm glad Boomer1986 got a resolution to his problem but what an ordeal!  Shame on GM.

Posted (edited)

a space shuttle costs about $450 million and blows up too in mid-flight.. 

 

I hear a light clunk every-now and then but doesn't bother me too much.  Is this a crew or ext cab, are you lead footed or light footed does that even make any difference?  I have an ext cab and i'm at 24k at the moment.  It heard it early on as few as 100 miles but doesn't happen much.  

 

To be honest, everything MAN MADE has issues.  btw, 1% of half a million trucks sold by GM is about 5,000 vehicles. 

Edited by cs2016lt
  • Like 1
  • 6 months later...
Posted (edited)

There is a class action law suit being initiated against GM for these faulty 8-speeds:

 

https://topclassactions.com/lawsuit-settlements/consumer-products/auto-news/869062-gm-class-action-alleges-hard-shift-transmission-defect/

 

I own a 2016 Sierra SLT that I purchased brand new. I've had these problems since the truck was new.  Took the truck back to GMC multiple times and the problem was never fixed.  

 

I contacted Cohen Milstein by email and requested I be listed in the lawsuit.  They said someone will contact me shortly to gather more information about my experience. 

 

If you are having problems with your 8-speed, I suggest you reach out:

 

Jamie Galucci @ [email protected]
Paralegal to Steven G. Calamusa, Esq.
4114 Northlake Blvd, Palm Beach Gardens, FL 33410
office: (561) 799-5070 fax: (561) 799-5040
www.fortheinjured.com

 

*************UPDATE*********************

 

Here is a link to the class action lawsuit 

 

francis-et-al-v-general-motors-llc.pdf

Edited by 16SierraSLT
Adding contact info
Posted
On ‎4‎/‎6‎/‎2018 at 12:06 PM, Abonino said:

Good Day All.

 

I own a 2016 GMC Sierra 5.3 V8 with equipped with the 8 speed transmission and 12,500 miles.  After about 6 months or so, I began to notice a distinct 'clunk' when upshifting at moderate to light acceleration.  Initially, I ignored it, since it was random and occurred relatively infrequently.   Since then, the hesitation & clunking has increased in frequency, especially on cold morning starts when taking the truck out after sitting overnight.  Subsequently, I did a search of this forum and others, and saw other 8 speed Sierra/Silverado owners were experiencing these same symptoms.

 

I then brougth the vehicle to two separate GMC dealerships for diagnosis and got the usual "we were unable to reproduce the problem", or "GM considers this normal operation" answers.

 

I then initiated a compliant with GM Customer Service, was assigned a case #, and over a month or so had to  escalate the issue twice due to slow response.  As of this morning, I was informed that:   "GM consders your complaint and description of symptoms as normal operation, therefore your case is being closed."

 

So, my question is this.   What is the consensus as to GM's current position on the 8 speed transmission performance issue as of this date?    The forum reseach I did earlier indicated a range of experiences including: "the dealer did nothing", "software reprogramming",  "a TSB will be forthcoming", "the dealer took apart my transmission apart",   etc etc.   I realize many threads exist on this topc.  I was hoping to get an update on recent experiences.

 

I just wanted to have my facts straight should I decide to continue the battle with GM.   My disappointment is rooted in the fact that the price sticker for my $57k truck didnt show transmission clunk as one of the options.

 

Thanks in advance.

wasting your time . I was just there today to do the trans flush with the Mobile 1 HP fluid. I was re assured by the service manager that he would do the so called fix. So I drop the truck off last nite. I called around 2 pm in the afternoon he tells me there was no shutter so the 18-NA-355 TSB cant be done. WTF I said my truck sat there all day after you tell me there doing this fix> Now you tell me its not being done. There reply was the transmission is normal operation. So they drove my truck 25 klm all day probably when for luch with it. kept it there all day only to tell me there are no updates which I already knew and no trans flush so basically a waste of time. there plain liers at the dealerships especially at the service departments. its all about how many customers they can reel in and rip off or charge GM under warrenty.

Posted

hello all i'm very disappointed with the lack of a repair for the 8 speed transmission clunk and hard shifts, they are random it is almost like there is electronic control issue causing the improper shift pressure in the transmission I would hope GM. Comes up with a fix for this issue restoring faith in them

Posted

I’d stick it in tow mode and see if it shifts smoother.  The gearing in tow mode seems to be better and more sporty IMO. 

Posted

I despised the 8sp on my former 2016 Sierra.  I could never get it to shift 'right.'  Then a tree fell on the truck and totaled it so I tested the new 10sp in a 2018 F-150 and was in love.  Then 6 months go by and the parking sensors never worked so Ford bought it back and I placed an order for a 2019 Denali 3500HD with the true Alison.  I should be happy now - not quite sure how the new 10 speeds on the HD's will turn out but I am happy with the tried and true Alison.

Posted

I hate that this is my response to this but truthfully, this is what I did.  I bought a 5yr/100,000mi bumper to bumper warranty.  The part I hate is that my plan is to get rid of the truck at 4yrs, 364 days or 99,999 miles.  I just don't want to deal with any auto dealer or manufacturer about the crap they put out and at least with the warranty, my financial exposure is capped.

 

The only other way I would own the truck is to accept that after 3yr/36,000 mile or more for the drivetrain, it's mine and I do what I want.  In that case, I'd be all over tricking out the truck, but I'd have the understanding that it's likely that running it hard will create a situation where I'd likely need to replace some major parts.  The offset would be that I'd keep the truck much longer.

Posted (edited)
On 2/14/2019 at 9:04 PM, benelli said:

wasting your time . I was just there today to do the trans flush with the Mobile 1 HP fluid. I was re assured by the service manager that he would do the so called fix. So I drop the truck off last nite. I called around 2 pm in the afternoon he tells me there was no shutter so the 18-NA-355 TSB cant be done. WTF I said my truck sat there all day after you tell me there doing this fix> Now you tell me its not being done. There reply was the transmission is normal operation. So they drove my truck 25 klm all day probably when for luch with it. kept it there all day only to tell me there are no updates which I already knew and no trans flush so basically a waste of time. there plain liers at the dealerships especially at the service departments. its all about how many customers they can reel in and rip off or charge GM under warrenty.

My dealership tried to tell me the same thing then I sent them this

https://techlink.mynetworkcontent.com/?p=11127

 

at the end of it it states this

 

Mobil 1 Synthetic LV ATF HP transmission fluid is required for all 8-speed transmission repairs regardless of the repair being completed.”

 

The new fluid is a requirement not an option for ALL 8 speeds. 

I told it to the service writer just like that ( and I was polite) . Bringing g it sat to get the new fluid. 

 

Edited by Neal90

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