2019 T1 8 speed Shifting

econometrics · May 11, 2019

Thanks, @bearded_warrior.

Yeah, it’s most definitely not acceptable for this to be a transmission “update” and still have the same issues the K2 8 speed did. I’m not very satisfied with that, either. Bad QA.

Coming from my 2007 4+OD, the whole thing feels strange to me. Even when it’s running smoothly. Ha!

I do plan to bring the trans up to my dealer in the near future. I’m hoping there’s a more standard fix for it by then.

bearded_warrior · May 13, 2019

So.. 120 miles since receiving from the dealer with classified "Normal Status".

I was out for a drive today, went backing out the driveway, accelerated to 20 mph, hard jolt on the shift (the hardest I have felt at this point) enough for my step-dad and I to start a discussion about the transmission on a 2k mile new truck. Pull up to the stop sign, come to a complete stop and start to lift my foot again to the gas pedal, WHAMMM! Truck slams into gear or something causing the truck to jolt forward about a foot before I put the breaks down hard again. We had to check the mirrors thinking we just got rear ended or something. Concerning because this could easily cause an accident.

Backed out of my families driveway and went to pull forward on the main road.. accelerated to 20-25 miles an hour. when the truck when to shift to second. WHAMMMMMMM!!!! The truck slammed into gear or something causing my wife and I to smack our heads against the backrests. It continued to slam through 3rd until we got up to speed. It was an extreme jolt, similar to feeling rear ended, hands down the hardest hardest shift or whatever it was I'd ever felt in a car. Way worse than the one above. The noise of the slam was so bad it sounded like a backfire or distant gunshot.

Couple notes, both incidents happened after coming to a complete stop before shifting from R -> D. Both times I had a warm vehicle, I'd already driven it for 45 min before either incident.

Calling the service department again tomorrow and setting up another appointment.

econometrics · May 13, 2019

Wow, that is alarming. Definitely needs to be seriously addressed by the dealer.

HondaHawkGT · May 13, 2019

3 hours ago, bearded_warrior said:

So.. 120 miles since receiving from the dealer with classified "Normal Status".

I was out for a drive today, went backing out the driveway, accelerated to 20 mph, hard jolt on the shift (the hardest I have felt at this point) enough for my step-dad and I to start a discussion about the transmission on a 2k mile new truck. Pull up to the stop sign, come to a complete stop and start to lift my foot again to the gas pedal, WHAMMM! Truck slams into gear or something causing the truck to jolt forward about a foot before I put the breaks down hard again. We had to check the mirrors thinking we just got rear ended or something. Concerning because this could easily cause an accident.

Backed out of my families driveway and went to pull forward on the main road.. accelerated to 20-25 miles an hour. when the truck when to shift to second. WHAMMMMMMM!!!! The truck slammed into gear or something causing my wife and I to smack our heads against the backrests. It continued to slam through 3rd until we got up to speed. It was an extreme jolt, similar to feeling rear ended, hands down the hardest hardest shift or whatever it was I'd ever felt in a car. Way worse than the one above. The noise of the slam was so bad it sounded like a backfire or distant gunshot.

Couple notes, both incidents happened after coming to a complete stop before shifting from R -> D. Both times I had a warm vehicle, I'd already driven it for 45 min before either incident.

Calling the service department again tomorrow and setting up another appointment.

You should try to record a video of it doing this stuff. It would be interesting to see it instead of going by a written account.

ct_corey · May 13, 2019

I drove a few 8 speed trucks before I got my custom trail boss. They all were nightmare to drive. The slamming downshifts were a huge turnoff. I drove my 6 speed trail boss and it shifted smooth as butter. Big reason why I bought it.

bearded_warrior · May 13, 2019

Threw together a quick video from the dash cam. (Pardon my editing skills)

https://youtu.be/JdBlMT7-zfQ - No Audio

The videos don't do what you feel in the car justice but it's better than nothing. Maybe it didn't go forward a full foot at the stop sign since my foot was still on the brake, it was hard to recall since it all happened so quick. It def gave us a smack.

bearded_warrior · May 15, 2019

Well, she's back in the shop again. Senior customer service escalated for repurchase/buyback which was denied at this time. They want to try to fix it first which is totally fair, discussions of taking it apart and seeing what they can find with the techs, field engineer will come out if needed.

I'll update with the outcome, hopefully we can get something useful.

FYI it looks like the Class Action has been updated to include the 2019's if it wasn't already.

http://gmauthority.com/blog/2019/04/gm-hit-with-class-action-lawsuit-over-alleged-8-speed-transmission-defect/

bearded_warrior · May 15, 2019

Update: Dealership opened up the TAC case today. They were told they are not authorized to do any work to the vehicle unless they themselves can repeat the issues, video or not. Of course they have had no luck repeating, just like last week when it was in there. There are no TSB's open except for the one that states hard shifts from 1-2 is normal while building pressure.

The service advisor is asking if he or the tech can take it home overnight to see if they can repeat anything. I'll be in touch with the Senior Customer Care rep again tomorrow. FWIW the Customer Care reps seem genuinely concerned about these issues and the experience, hopefully they can override anything preventing them from looking into the transmission.

econometrics · May 16, 2019

Good to know. Thanks for the updates! Hope the trans can act up for them, so they can see it / feel it first hand.

175vTrailbossLT · May 28, 2019

I am pretty glad I found this thread. I thought I was imagining things when I get what I believe to be the same “transmission slip/jerk” feeling. I have had it a couple times right after initial start up and drive off (I take it very easy when first driving off from a start). After some quick research, this 8 speed had been around since the previous 2014+ generation correct? But the solution seems to be “well that’s how it is”. Kind of weird. I guess that’s what warranty is for right, in case something major does go wrong?

Sent from my iPhone using Tapatalk

econometrics · May 28, 2019

12 minutes ago, 175vTrailbossLT said:

I guess that’s what warranty is for right, in case something major does go wrong?

That's right. This is why I have not taken my RST in. First, the shifting issues for me have gotten MUCH better as I've added up mileage. I'm at 2300 right now and have had very smooth shifts, outside of the normal, abrupt 1-2 shifts when it's cold sometimes.

And, yes, this 8-speed was updated with a new torque converter for 2019. The 8 speed existed in the K2 (previous generation) trucks.

Moend · May 29, 2019

On 3/26/2019 at 3:03 PM, bearded_warrior said:

Hello,

Has anyone else experienced any shifting issues on their 2019's? The big one I seem to get a hard shift point around 2-4k RPM coming off a stop under light gradual acceleration shifting from 1st to 2nd gear. It's fairly random but seems to be more common after the transmission heats up 150-160 degrees or more, though it'll happen cooler too. The other is when feathering the throttle in traffic the downshifting seems a little harder than it should be, not as hard as the upshift and it doesn't clunk like my old 16' but it's a feeling like driving over a small bump occasionally but it's happened enough while watching the RPM needle shift to think it's not just the coincidence of running over a little bump. Typically during low traffic speeds < 30mph.

All in all, the transmission is a vast improvement and is way smother compared to my clunky 2016 5.3L 6 speed Z71 which I traded in with 35k miles after valve sticking issues and a transmission rebuild replaced a fair bit of the transmission (torque converter, valve body, transmission pump).

I cant tell if i'm just sensitive to the transmission or if I have something worth pursuing, service department says to give it 1500/2000 miles while the truck is "learning" as mentioned in other threads, I currently have just shy of 1100. After that I dread the "normal behavior" discussion.

Overall it's a great truck, really smooth overall and a beast on the open road, in fact it's so smooth most of the time I think it might make the slow speed hiccups seem worse than they are. It's just a concern knowing that if it starts shifting issues at 500 miles, what's it gonna be doing at 20k miles etc..

Thanks everyone for reading! What's your experience?

2019 Silverado 5.3 V8, 4x4, Z71, RST

I have similar truck. Everything -RST, anyway sometime on startup and pulling out of work (going forward) I get a clunky noise kind of remind me of a slip yoke issue I had on my 2000 Silverado years ago. And another occasion after dropping off 9000lbs trailer then backing up for 20 ft then switching to drive it clunked again. Same thing this time a noise reminds of slip yoke issue. Aside from these to instances I haven't experienced anything else. My father 16 with 6 speed feels as smooth as my 19 but the 19 feels faster

dj13990 · June 7, 2019

On 5/15/2019 at 4:59 PM, bearded_warrior said:

Update: Dealership opened up the TAC case today. They were told they are not authorized to do any work to the vehicle unless they themselves can repeat the issues, video or not. Of course they have had no luck repeating, just like last week when it was in there. There are no TSB's open except for the one that states hard shifts from 1-2 is normal while building pressure.

The service advisor is asking if he or the tech can take it home overnight to see if they can repeat anything. I'll be in touch with the Senior Customer Care rep again tomorrow. FWIW the Customer Care reps seem genuinely concerned about these issues and the experience, hopefully they can override anything preventing them from looking into the transmission.

Any update on your truck? Today starting at a stop sign the transmission slammed so hard I thought I got rear ended. Then after that it was smooth all day. Just wondering if they have found anything or did a fix for you?

bearded_warrior · June 8, 2019

Unfortunately I have nothing good to report and it's back in my possession.

TLDR; I think I have to go lemon law, I've had it in the shop two times (Going back Monday), 25 days, and have a safety concern because the transmission will lurch hard making it feel like you were rear-ended causing a hard whiplash feeling and the car jumps forward. Zero Support from GM TAC Case, no work authorized unless dealership can repeat with computer hooked up.

Dealership has put ~350 miles on the truck and is unable to repeat any conditions besides what is defined in the TSB for hard 1-2 after start. I've had the truck back since Tuesday and driven it twice. (I've been using the motorcycle to get around)

Here's what I logged from my 2.5 hour round trip commute on Thursday. (Sloppy voice to text notes)

-------

Hard 1st to 2nd at 8:12 a.m. temperature is 185 degrees Fahrenheit today is June 5th. From stop steady throttle No hard acceleration Auto Stop disabled. Was driving for approximately 50 minutes
Rough shift 1st to 2nd 8:20 a.m. fluid temperature 183 degrees Fahrenheit same conditions above
Very hard shift first to second 154 degrees Fahrenheit transmission fluid at 3:53 p.m. external temperature 84 degrees driving time 20 minutes approximately 2500 to 3,000 RPMs

------

But wait... There's more, the truck lurched again today coming to a stop at a crosswalk. I'm completely out of ideas of what to do here or what it could be that's causing all this. 74 degrees outside, 25-30 min drive time, 155 degrees transmission temp. Ran into the store for 5 min and was leaving the shopping center.

Side note; dealership has been very understanding and impressively dedicated to trying to repeat these issues. GM customer care has tried their best and my Customer Care Rep has been awesome, but she literally cannot do anything else. The District Manager is not doing anything until there is a repair attempt, which GM won't authorize.

I miss manuals.

dj13990 · June 8, 2019

Thanks for the update. Sorry to hear they haven't done anything yet. I haven't had it happen again, fingers crossed. Maybe the more of us that report the issue the more GM will do. Please keep us posted on anything you do or if GM does anything else.