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Posted
4 hours ago, ajensen383 said:

One new thing that happened over the weekend...This only happened once so im not sure if it will be an on going issue... Driving home on the highway, pulling a light grade in 8th gear.. I went to pass a truck so I gave it some gas. Usually It will downshift into 7th and then when I let up it will go back to happily chewing along in 8th...This time it felt strange in the downshift, not even sure how to explain it, like it was caught in between gears and wasn't a firm downshift as usual, almost soggy feeling . It would not shift into 8th not matter what until I crested the grade. I tried going almost 80 and letting off slowly to make it shift, I tried manually putting it in 8th, nothing would get it to shift... After I crested the grade  it was fine after that but wondering if it will happen again...

Were you in Tow-Haul mode maybe?

Posted

Got my 2017 6.2 back 2 days ago after getting the dealer to flush with the new fluid. I've only put about 100 miles on it but so far no shudder. The truck has 34k miles now and the trans has never felt this good. The truck has been to the dealer about 5 times for the trans acting up. They usually just update and perform a trans relearn which didn't ever help. This is the 2nd time they've flushed the trans. The 1st time they flushed it helped but still had the occasional shudder. Now it feels like they finally fixed it.

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  • Like 1
Posted

A few NMD red miles after the fluid swap ....

 

Upshifts from stopped feel a bit more prounounced when first starting out ... less so after awhile (thinning fluid as trans fluid temp rises?)

 

As I brake approaching stoplights, I keep waiting for the big CLUNK I used to get - between second and first? Kinda feels like I wants to clunk but doesn’t.

 

No shudder of any kind at any speed ...

  • Like 1
Posted

Is the fluid swap an option for the 6 speed? Any TSB’s?


2015 Silverado LT Midnight Edition
4.5” CST suspension lift
Sent from my iPhone using Tapatalk

Posted
On 1/13/2019 at 7:08 AM, bigman32hockey said:

My brand new '18 Redline Editon developed "the shudder" at around 450 miles.  Mine seems to shudder worst when around 50 mph and constant speed and again between 65-70 mph, where it will do it all the time.  I went to my dealer and was told GM will not reimburse them when they install new torque converters for this issue.  Apparently GM has issued a document (Document ID: 4536930) which says GM engineering has proven the problem is not caused by the torque converter.  The only fix my dealer can offer is the transmission fluid flush and fill with Mobil 1 synthetic.  I know this won't fix the shudder problem, but at this point I have to go through the steps GM offers.  I honestly cannot believe I am having this problem.  I had a '17 Midnight Edition that I traded up from (wanted the 6.2L engine and a few other options).  That truck ran perfectly.  Never had any problems with it.  Less than 1,000 miles on the new one and I regret the day I drove off the lot with it.  Now every time I see another Silverado on the road, I wonder to myself, "I wonder if their truck drives correctly?"  It is ridiculous that a $60,000 truck rides like crap.  I mean, how can GM expect me to be satisfied with this purchase?  If this problem isn't fixed after three attempts, which I doubt it will, I will be hiring a lawyer and proceeding with a Lemon Law claim.  For GM just to say they are aware it's a problem but don't know how to fix it is not acceptable.  Are others out there in the same situation as me?  If you got your's fixed, how exactly did you do it?  Thanks.   

I have a 2018 GMC 6.2L 1500 does the shudder just took it to dealership the manager calls me and says there is nothing wrong with the truck.   I'm picking it up in morning.  Afraid I'm going to lose my shit on these crooks. Shakes like hell everyone that's ever ridden in it mentions it.  We'll see what happens tomorrow. 

Posted
On 1/18/2019 at 9:51 AM, ajensen383 said:

I have to agree with this.... You usually only hear about the bad ones...although there are a lot of people that may or may not have issues that don't know about this forum either.. But this does sound like a pretty big problem for GM since its not only our trucks..Camaro and Corvettes have the same problems..

 

I have my 2018 truck about a year now and 8500 miles and I don't have any issues with mine... My only real complaint is when doing a rolling stop and getting back on the gas it will act like its in neutral ( rpm goes up while coasting ) then slam into 1st... if I actually stop, there are no issues... I tried different speeds on the highway and no shuttering at all...so far

 

Just throwing it out there my 2018 was built in 11/2017 , not sure if time of build has anything to do with it

 

I know the 2015-2016 trucks had a lot more issues than the 2017-2018 models do., but I wonder how many 2018 models have this issue?? Most of the posts on here are 2015-2016 trucks, there are not too many specifically on the 2018s yet.

2018 GMC 6.2L Sierra shakes bad, dealer told me it's normal.  Picking it up in morning. 

Posted
Is the fluid swap an option for the 6 speed? Any TSB’s?


2015 Silverado LT Midnight Edition
4.5” CST suspension lift
Sent from my iPhone using Tapatalk


Are you having issues with your 6 Speed?


Sent from above
Posted


Are you having issues with your 6 Speed?


Sent from above

Yeah it has its problems here and there


2015 Silverado LT Midnight Edition
4.5” CST suspension lift
Sent from my iPhone using Tapatalk
Posted

Yeah it has its problems here and there


2015 Silverado LT Midnight Edition
4.5” CST suspension lift
Sent from my iPhone using Tapatalk


I’ve heard that the 14-15 warranty is longer and goes further on your transmission versus my 18. It should state it in your owners manual.


Sent from above
Posted (edited)
1 hour ago, TXGREEK said:

 


I’ve heard that the 14-15 warranty is longer and goes further on your transmission versus my 18. It should state it in your owners manual.


Sent from above

 

GM used to have a 5/100k powertrain warranty, however they knocked it down to 5/60k in either '14 or '15

Edited by jimmyboy8301
Posted


I’ve heard that the 14-15 warranty is longer and goes further on your transmission versus my 18. It should state it in your owners manual.


Sent from above

I will check it out. Took it into dealer before to have it checked. Left it for the day and I was told my oiled k&n Cai is the problem. They say oil probably got on the MAF. They didn’t even take my truck for a test drive. So I was told to put stock air intake back on they will clean the mAF and then do a trans relearn. Still haven’t taken it back yet.


2015 Silverado LT Midnight Edition
4.5” CST suspension lift
Sent from my iPhone using Tapatalk
Posted

I will check it out. Took it into dealer before to have it checked. Left it for the day and I was told my oiled k&n Cai is the problem. They say oil probably got on the MAF. They didn’t even take my truck for a test drive. So I was told to put stock air intake back on they will clean the mAF and then do a trans relearn. Still haven’t taken it back yet.


2015 Silverado LT Midnight Edition
4.5” CST suspension lift
Sent from my iPhone using Tapatalk

How many miles do you currently have?


Sent from above
Posted

How many miles do you currently have?


Sent from above

47K


2015 Silverado LT Midnight Edition
4.5” CST suspension lift
Sent from my iPhone using Tapatalk

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