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Who likes their 8 Speed?

JacobC1983
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m3n00b Enthusiast

m3n00b

Posted
Posted (edited)

What's "flair shift"? Just curious.

It's slow to shift from 1st to 2nd when cold. Usually only once per day. It allows the rpms to climb between the shift and causes a mild jerk when it finally gets into 2nd.

 

-tapa

Edited by m3n00b
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JacobC1983
JacobC1983

I care about warranty.... It pays for repairs that otherwise I would have to pay for out of pocket. Actually, lots of people care about warranty on a $50k+ vehicle.

mitchellb2005
mitchellb2005

I love my 8 speed. I never hate it, but sometimes it does small annoying things, but I expected an 8 speed to be a little finicky sometimes since I also have an 8 speed in my Audi A7. Once you learn w

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jlilnc14 Enthusiast

jlilnc14

Posted
Posted

It's slow to shift from 1st to 2nd when cold. Usually only once per day. It allows the rpms to climb between the shift and causes a mild jerk when it finally gets into 2nd.

 

-tapa

I've discovered that after the truck has been sitting a while, Shift into drive and let it coast for a few feet( it redistributes the oil in the trans) then slowly accelerate after. The jerk is either really mild or totally gone, depending on how long you coast. I usually just coast out of the garage and another 10 feet and usually there's no jerk. I plan on getting the TSB done to fix this when I go in for my first free service.

mookdoc6 Senior Enthusiast

mookdoc6

Posted
Posted

Is there is a TSB for this? I have exact same issue? I am in shop at moment to see what's up with the 1st to 2nd when cold?

jlilnc14 Enthusiast

jlilnc14

Posted
Posted

Is there is a TSB for this? I have exact same issue? I am in shop at moment to see what's up with the 1st to 2nd when cold?

TSB #16-NA-014 : Delayed Engagement after sitting with the engine off. 2015-2015 models.

mookdoc6 Senior Enthusiast

mookdoc6

Posted
Posted

Thanks! I had what the dealer called a Fast Learn C4Clutch packs/Pads softening. And so far this baby is Spot On!

CptMcSaug Enthusiast

CptMcSaug

Posted
Posted

Been without mine for a week getting torque converter number 2 put it. Hope this fixes the shuddering...

mookdoc6 Senior Enthusiast

mookdoc6

Posted
Posted

Been without mine for a week getting torque converter number 2 put it. Hope this fixes the shuddering...

Hope so too bud! You might have been the lucky one to get both batches of shitty torque converters?

  • 2 weeks later...
Croak Enthusiast

Croak

Posted
Posted

Had the delayed shift problem, but the dealer did a re-learn and the truck was great for a week or so. Started to feel a little lazy again after that. The re-learn didn't fix the occasional clunky downshift, especially with the shifter in M mode. Now it's started to fluctuate RPM at steady cruise around 40mph under light load - revs will climb a couple hundred RPM then drop again, keeps doing this. Truck has also developed a shudder through the whole drivetrain under a few circumstances, haven't figured out what triggers it yet. Guessing something is truly broke now. Will head to the dealer this week and hope they don't try to blame it on my dropped suspension.

  • 2 weeks later...
powerhaulic Enthusiast

powerhaulic

Posted
Posted

Been without mine for a week getting torque converter number 2 put it. Hope this fixes the shuddering...

How did you make out with new converter?

powerhaulic Enthusiast

powerhaulic

Posted
Posted

Had the delayed shift problem, but the dealer did a re-learn and the truck was great for a week or so. Started to feel a little lazy again after that. The re-learn didn't fix the occasional clunky downshift, especially with the shifter in M mode. Now it's started to fluctuate RPM at steady cruise around 40mph under light load - revs will climb a couple hundred RPM then drop again, keeps doing this. Truck has also developed a shudder through the whole drivetrain under a few circumstances, haven't figured out what triggers it yet. Guessing something is truly broke now. Will head to the dealer this week and hope they don't try to blame it on my dropped suspension.

That is converter shudder

Occurs light throttle light load.

I'm thinking the additive package in the new spec Dexron HP is greatly at fault, combined with software....JMHO

CptMcSaug Enthusiast

CptMcSaug

Posted
Posted (edited)

How did you make out with new converter?

To be honest it actual feels alot better.

 

The truck is shifting better, smoother and quicker. No more shudder under light load. The RPMs don't fluctuate up and down cursing anymore. Truck feels quicker and is average 1 mpg more. Now the test will see if it last.

Edited by CptMcSaug
  • Like 1
silver sled 16 Enthusiast

silver sled 16

Posted
Posted (edited)

Hello all this is my first post here. I found and joined this site due to my ongoing issues with my 8 speed. It's been bad since the ride home from dealer. I had the converter replaced at 700 miles. That took care of the shuddering but I'm still left with awful shifts up and down. Only occurs when driving smoothly. Truck has 3700 miles on now and seams to be getting worse. Fuel milage is down too. Truck is 100%stock. Towing and leaning into it is awesome. Truck is a rocket ship. Dealers have been no help. "OPERATING AS DESIGNED" is what I get. No updates as of yet. Gm customer service sas bring it to dealer. Well after 10 new gm cars and trucks in past 15 years between me and my wife im little disappointed. Please help gm. I know it's in the programming. I myself am an nissan dealer mechanic. Nissan has similar issues that are usually repaired timely and simply with reprograms. Seams this issue spans years of production. What's going on,???

Edited by silver sled 16
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