6.2L 8 Speed OWNERS! GM UPDATE 15389

440hsp · June 3, 2015

If things don't get any better after the update I will get an intune and contact diablew.

Stoddard · June 3, 2015

Mine has improved a bit, but low speed driving is worse than before. The 1->2 shift from a stop at low acceleration has a huge delay in the shift, then surges about 300 RPM, then comes back down, making the truck jerk. Other times, I can be cruising at about 40mph, and watch the tach surge and drop a few hundred RPMs continuously making the truck jumpy. I am going to drive it a bit more to see if it gets smoother. If not, back to the dealer, and a certified letter off to GM.

Is this after this update?

Jordan18 · June 3, 2015

Mine goes in on Friday for this, then I won't judge it until I put another 1000 miles on to gauge if it is actually better.

I had no complaints really other than the odd hard downshift coming to a stop, might be just a 8 speed thing to get used to.

SkiDooNick700 · June 4, 2015

I had this update done a week ago with about 200 miles on the clock. I've driven about 150 since then. Shifts seem a little firmer, I like it.

I just experienced some Craziness today though... not sure what was going on, has anyone experienced this? I am not blaming the update by any means.

Quoting from a text i sent my friend today...

Just experienced some massive shuttering with my trans. Leaving the gym, put it in drive, wasn't moving on its own so i give it a little gas it starts shaking and shuttering and so I left off, stop, go to neutral, back to drive, still not moving on its own, give it a little gas, shaking and shuttering again and then the RPM started going up like I'm free reving the engine. Back to neutral, back to drive, all is fine.

I've drive the truck about 5 miles with multiple restarts since this happened and had 0 issues. Trans is smooth as it always has been. Some random hiccup?

EDIT: i should mention mine is a 4/27/2015 build

Jordan18 · June 4, 2015

I had this update done a week ago with about 200 miles on the clock. I've driven about 150 since then. Shifts seem a little firmer, I like it.

I just experienced some Craziness today though... not sure what was going on, has anyone experienced this? I am not blaming the update by any means.

Quoting from a text i sent my friend today...

Just experienced some massive shuttering with my trans. Leaving the gym, put it in drive, wasn't moving on its own so i give it a little gas it starts shaking and shuttering and so I left off, stop, go to neutral, back to drive, still not moving on its own, give it a little gas, shaking and shuttering again and then the RPM started going up like I'm free reving the engine. Back to neutral, back to drive, all is fine.

I've drive the truck about 5 miles with multiple restarts since this happened and had 0 issues. Trans is smooth as it always has been. Some random hiccup?

I thought I read somewhere on here of someone having a similar issue. I would just make a note of it for now and if it continues send it back to the dealer.

CounterMeasure · June 4, 2015

Is this after this update?

Yes. Its worse if the transmission is cold, but then, both transmissions in my truck have always been worse when cold. Its like the cold shift tables are filed with "eh, screw it, its friday" values.

Rme2513 · June 4, 2015

I thought I read somewhere on here of someone having a similar issue. I would just make a note of it for now and if it continues send it back to the dealer.

i know if I go stright to drive with out letting it prim up for a few seconds ( 5 to 10 ) it will do that like its slipping then it will grab and be jerky now I just wait a few seconds I'm not happy with it but now that I know it is not just mine I'm ok with it

Chuckstermania · June 9, 2015

I received my 2015 Denali with the 6.2L 8 Speed in November of 2014. At 1150 miles the transmission had to be replaced. It lost significant power in forward and reverse did not work at all. Now the truck has just under 2500 miles on it and if I slow down to a few MPH and do not come to a complete stop, it will shift very hard when I start to accelerate.

lba0213 · June 9, 2015

Anybody get an email like this today? or Recently?

2015 CHEVROLET SILVERADO K15 CREW CAB VIN #3GCUKSEJ7FG230213

RECALL #2015389 TORQUE CONVERTER CLUTCH (TCC) SHUDDER (NO PARTS)

RECALL #2015216 PROPSHAFT U-JOINT RETAINER BOLTS LOSS OF INDEX (PARTS - NEED TO ORDER)

To keep your vehicle in optimal condition, we have factory trained technicians at Universal Chevrolet Co Inc that can take care of this recall for you. Once the parts are here it will take about 3 - 3 1/2 hours to fix these recalls for you.

Our Service Department is open Monday - Friday 7:30 am - 5:30 pm with extended hours on Tuesday and Thursday 7:30 am - 7:30 pm.

You can either respond to this email regarding a time which works best for you or, you can contact me directly at 919-365-6351 to set up a time for you to come in.

Thanks again for choosing Universal Chevrolet Co Inc for your vehicle service needs.

Perhaps GM has finally figured out the cause and developed a fix for it????

Jordan18 · June 10, 2015

Anybody get an email like this today? or Recently?

2015 CHEVROLET SILVERADO K15 CREW CAB VIN #3GCUKSEJ7FG230213

RECALL #2015389 TORQUE CONVERTER CLUTCH (TCC) SHUDDER (NO PARTS)

RECALL #2015216 PROPSHAFT U-JOINT RETAINER BOLTS LOSS OF INDEX (PARTS - NEED TO ORDER)

To keep your vehicle in optimal condition, we have factory trained technicians at Universal Chevrolet Co Inc that can take care of this recall for you. Once the parts are here it will take about 3 - 3 1/2 hours to fix these recalls for you.

Our Service Department is open Monday - Friday 7:30 am - 5:30 pm with extended hours on Tuesday and Thursday 7:30 am - 7:30 pm.

You can either respond to this email regarding a time which works best for you or, you can contact me directly at 919-365-6351 to set up a time for you to come in.

Thanks again for choosing Universal Chevrolet Co Inc for your vehicle service needs.

Perhaps GM has finally figured out the cause and developed a fix for it????

Negative on the email, just took the number from this thread to them and they did it without question.

That propshaft recall seems new however, wonder when it came out.

Higgs Boson · June 10, 2015

my dealer's service dept told me about both of these recalls last week when they installed my long tube headers. i am taking it in tomorrow AM so they can put on my magnaflow catback and do both of these recalls (they had to order the bolts).

440hsp · June 10, 2015

my dealer's service dept told me about both of these recalls last week when they installed my long tube headers. i am taking it in tomorrow AM so they can put on my magnaflow catback and do both of these recalls (they had to order the bolts).

Your dealer installed your headers??? No voided warranty?

salem185 · June 10, 2015

2015 silverado high country 6.2 tested after the third time in GM dealer for transmission shifting problem after the recall done become worst than ever.

its only done 1600 miles.

Higgs Boson · June 10, 2015

Your dealer installed your headers??? No voided warranty?

why would they void my warranty if nothing is broken? the whole voided warranty thing is so dumb. if something breaks caused by a lean condition from installing the headers (which would be like a burned up piston or valve or something) then then GM (not the dealer) can deny my warranty claim (if I was dumb enough to want it fixed under warranty, which I am not).

it's totally illegal to simply "void your warranty." all they can do is deny your claim on a case by case basis. your next warranty claim could be completely valid. the headers are not going to cause a loose bolt in my throttle body to pop out and kill a cylinder, etc....headers are also not going to cause a transmission failure as the A8 is rated to what, 837 ft lbs or something?

I'm not worried about that at all.

440hsp · June 10, 2015

why would they void my warranty if nothing is broken? the whole voided warranty thing is so dumb. if something breaks caused by a lean condition from installing the headers (which would be like a burned up piston or valve or something) then then GM (not the dealer) can deny my warranty claim (if I was dumb enough to want it fixed under warranty, which I am not).

it's totally illegal to simply "void your warranty." all they can do is deny your claim on a case by case basis. your next warranty claim could be completely valid. the headers are not going to cause a loose bolt in my throttle body to pop out and kill a cylinder, etc....headers are also not going to cause a transmission failure as the A8 is rated to what, 837 ft lbs or something?

I'm not worried about that at all.

True. Just a little edgy about installing some ARH's on my 6.2. But want them badly so I might just say screw it. Do you have a tune on your truck?