2019 T1 8 speed Shifting

[JR09country]

 
Without an indication in the dash? I set mine every night at home (driveway is inclined). But last night I was totally level when parked. No light on the dash. Had to apply some gas to get it going. 

I noticed this to when I go to pull out of the garage. I didn't think about the parking brake automatically engaging, I figured it was the hill start assist. But why wouldn't it do it when I place the truck in park, I still get some roll forward after putting it in park. Hmm

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[Stex]

On ‎4‎/‎21‎/‎2019 at 11:11 AM, Bikeman said:

I have 1500 on mine and the only time I notice the 1-2 clunk is when the trans isnt warmed up. I'm thinking hard shifts are a characteristic of the 8 speeds. I traded in a 16 with the 8 spd and the 19 is noticeably smoother and the weird whistling sound the 16 had is not present in the 19? Idk

GM has had a lot of trouble with the A8 torque converter. The Camaro folks have a long thread on A8 shifting and T/C shudder.

GM has a TSB out for a new fluid for the A8 to solve the issues. Too early to know if it is the solution. IF I Had and A8 I would make sure it has the new fluid in it. I would have GM change it out EVEN if I had to pay for the fluid exchange.

 

https://www.camaro6.com/forums/showthread.php?t=548026

 

https://www.camaro6.com/forums/showthread.php?t=525175

 

[bearded_warrior]

5 hours ago, Stex said:

GM has had a lot of trouble with the A8 torque converter. The Camaro folks have a long thread on A8 shifting and T/C shudder.

GM has a TSB out for a new fluid for the A8 to solve the issues. Too early to know if it is the solution. IF I Had and A8 I would make sure it has the new fluid in it. I would have GM change it out EVEN if I had to pay for the fluid exchange.

Funny that you mention this, I filled out my survey with Chevrolet the other day and just got a call back from their customer service department, they're trying to schedule a transmission fluid flush for me, there's a TSB that came out for some of these trucks in February. It was mentioned that behavior from the fluid can be confused with the "break in period". 

 

I am happy to see that the survey didn't just fall to the wind. 

 

 

* Supposedly the T1's use L890 (M5U) Transmission but I wouldn't be surprised if they had the same issues as the A8.  -  http://gmauthority.com/blog/gm/gm-transmissions/m5u/

 

[econometrics]

24 minutes ago, bearded_warrior said:

* Supposedly the T1's use L890 (M5U) Transmission but I wouldn't be surprised if they had the same issues as the A8.  -  http://gmauthority.com/blog/gm/gm-transmissions/m5u/

 

The T1's use the MQE 8-speed. It's an "improved" / revised 8L90. 

 

http://gmauthority.com/blog/2018/07/gm-8-speed-automatic-enhanced-for-2019-silverado-sierra/

http://gmauthority.com/blog/gm/chevrolet/silverado/2019-chevrolet-silverado/2019-chevrolet-silverado-powertrain/2019-chevrolet-silverado-transmissions/

Edited April 23, 2019 by econometrics

[bearded_warrior]

2 minutes ago, econometrics said:

The T1's use the MQE 8-speed. It's an "improved" / revised L890. 

 

http://gmauthority.com/blog/2018/07/gm-8-speed-automatic-enhanced-for-2019-silverado-sierra/

http://gmauthority.com/blog/gm/chevrolet/silverado/2019-chevrolet-silverado/2019-chevrolet-silverado-powertrain/2019-chevrolet-silverado-transmissions/

 

Thank you, that's right. I followed the outdated links on http://gmauthority.com/blog/gm/gm-platforms/t1/

[Stex]

Yes, looks like a new design for the T/C too. That was the fluid flush issue. Anyone have the TSB bearded_warrior mentions above?

[bearded_warrior]

My service advisor said the TSB was removed for some reason and he can no longer find it. Hopefully it's just being updated. I heard them use the term "Triple Fluid Flush" when describing the TSB. 

[econometrics]

My RST 8-speed really changes its mind a lot, from what I have noticed over the past week of driving it around. 

 

Some days, it shifts super smooth. Other days, there's a harder shift from 1-2. The next day, that's gone and it's instead a harsh downshift from 3-2 or 2-1. Still other days, it's an abrupt 2-3 shift. 

 

So strange. 

 

None of these are really all that concerning to me, though. I would still say my transmission delivers smooth power overall. I think part of my noticing is that I'm paying very close attention to it. 

 

When I notice it the least is when I really apply power to the engine with some assertiveness on the gas pedal. Babying it and anticipating the shift changes with my foot seem to produce the most harsh shifts. 

[Mdsjohna]

Ford was right not to use this transmission looks like it’s a crap design.

[Stex]

On ‎4‎/‎24‎/‎2019 at 5:34 PM, bearded_warrior said:

My service advisor said the TSB was removed for some reason and he can no longer find it. Hopefully it's just being updated. I heard them use the term "Triple Fluid Flush" when describing the TSB. 

That was the old TSB method. The new TSB for the A8 is to put in the NEW  formulated type Trans fluid.

 

Based on comments above, it looks like the 1500s, not the subs,  '19 A8 has a redesigned/modified/updated  trans and TC. Surely , don't call me Shirley, it has the latest part number fluid. See the Camaro C-6 forum for much more specific info, like the new fluid part number and TSB # for the new fluid flush.

[HondaHawkGT]

On 4/25/2019 at 10:50 AM, Mdsjohna said:

Ford was right not to use this transmission looks like it’s a crap design.

Ford never planned on using the GM 8L90. They have their own crap 10R80 transmission which has just as many complaints as the 8L90 does.

https://www.youtube.com/results?search_query=f150+10+speed+transmission+problems+

https://www.youtube.com/results?search_query=10R80+problems

Edited April 27, 2019 by HondaHawkGT

[HondaHawkGT]

6 hours ago, Stex said:

That was the old TSB method. The new TSB for the A8 is to put in the NEW  formulated type Trans fluid.

 

Based on comments above, it looks like the 1500s, not the subs,  '19 A8 has a redesigned/modified/updated  trans and TC. Surely , don't call me Shirley, it has the latest part number fluid. See the Camaro C-6 forum for much more specific info, like the new fluid part number and TSB # for the new fluid flush.

Yes the new TSB is 18-NA-355 though it may not cover the revised 8L90 design in the 2019 trucks.

[bearded_warrior]

I just got mine back from the shop.

 

TLDR; "NORMAL"

 

They Referenced: SI Doc 4605342 - 1-2 shift on cold trans considered normal.

 

Even though mine shifts hard when warm and more gears than just 1-2. Test drive and TAC Case was deemed normal. 

 

Regarding the transmission, there were no attempted "fixes" "flushes" or anything. They also mentioned that the software is "restricted" to their techs so not even they can look to see if it's the latest version. 

 

 

This is like Deja Vu with my 16' which had a transmission rebuild at 3 years 35k miles.  Though I will say, compared to the 19' 6 speed 1500 Custom I had as a loaner, my19's 8 speed feels majorly smoother.  

[econometrics]

This is why I am not even going to bother to take my truck in for service on the 8 speed. 

 

Sure, I notice a few odd shifts from time to time, but after 1600 miles now, I really feel like it's smoothing out a lot. 

 

I honestly think a big part of it is me not attempting to notice every little harsh shift by paying special attention to it. As I have just stopped thinking about it and enjoyed the truck, I've noticed it less. Sometimes I think we can all be a little hypochondriac with our new, expensive trucks. ;) 

[bearded_warrior]

@econometrics, I see what you're saying, and you're 100% right, we're being a little over attentive to our brand new trucks. Some of us came from the 14-19 LD platform, had a variety of issues, and were hoping for something... better...

 

But as you've said, new platform, new issues which brings new "fixes".  I'm glad yours has smoothed over time, but in my case (at 2k miles), it seems smoother one day and then later that day or the next it's rough shifts up to 4th or 5th, and odd downshifts when coming to a stop and nothing I can seem to do makes a difference.

Just because something is considered "normal" doesn't mean it's right. If I didn't say anything before, i'd be driving a truck with a broken Torque Converter and Pump and Valve body.

 

It's taken over 3 years for this to come out - http://gmauthority.com/blog/2019/04/gm-hit-with-class-action-lawsuit-over-alleged-8-speed-transmission-defect/. 

 

I'd love to hope that was all fixed itself before the T1 gen 8 speeds. I'm just more of a skeptic I suppose. :-)

 

Again best of luck to you and your truck, hopefully the rest of us who have issues can get a little of that smoothing out you're finding :-D.