6.2L 8 Speed OWNERS! GM UPDATE 15389

newdude · May 26, 2015

I can pull up the recall, but when I "click" on it, it just reads "no information available at this time for this bulletin or campaign". I usually gives me pages of info. So no matter who I was looking it up for, recall 15389 doesn't give me any info.

You work at a dealer? Check your Global messages, search 8L90.

General Motors is releasing Service Update Bulletin 15389 today. The total number of U.S. vehicles involved is approximately 54,037.

SILVER SLED · May 27, 2015

It's all there this am.

Rme2513 · May 27, 2015

Good luck! Let us know how it works out!

Just FYI, you're about to get ate up by those swearing up and down that these transmissions can't "learn".

i was told by my service manager that they don't learn and that was after they installed my replacement 8 speed transmission

dapersico · May 27, 2015

I took my 2015 Sierra Denali 6.2L/8-Speed in this morning for something else and they told me I had a recall. I did not bring it in for the trans or even tell them about. They said it was for the 8-speed transmission shudder. I will have it back later today with the recall performed.

My wife's 2015 Yukon Denali is also showing the recall.

Dwayne

Rme2513 · May 27, 2015

I have been post in another form but I will ask here to. When I crank it up cold and shift stright to drive if I don't let it sit there for a 5 to 10 seconds it will not pull off it just slips dose yalls do this also ?

P-Funk · May 27, 2015

I have been post in another form but I will ask here to. When I crank it up cold and shift stright to drive if I don't let it sit there for a 5 to 10 seconds it will not pull off it just slips dose yalls do this also ?

Mine hasn't done that before, but I may not go into drive that quickly. I usually turn the truck on, then put my seat belt on, and then put it in to drive.

CounterMeasure · May 27, 2015

I have been post in another form but I will ask here to. When I crank it up cold and shift stright to drive if I don't let it sit there for a 5 to 10 seconds it will not pull off it just slips dose yalls do this also ?

Mine doesn't "slip" in the traditional sense, but it does not "engage" right away. I've had to retrain myself from my last truck because of it . Now, I start it, wait for the gauges and whatnot do to their thing, and then shift into drive. Otherwise, the transmission engagement will happen at some point well after putting it in drive but be a jolt if I've given it gas before it was actually ready..

Rme2513 · May 27, 2015

Mine doesn't "slip" in the traditional sense, but it does not "engage" right away. I've had to retrain myself from my last truck because of it . Now, I start it, wait for the gauges and whatnot do to their thing, and then shift into drive. Otherwise, the transmission engagement will happen at some point well after putting it in drive but be a jolt if I've given it gas before it was actually ready..

Yes that is similar but I have got in not thinking about it and crank up and go and did not wait and it actually sounds like meatal on meatal. I have had a lot of automatic transmission befor and never have had this problem but it's good to know it is not just mine

CounterMeasure · May 27, 2015

Yes that is similar but I have got in not thinking about it and crank up and go and did not wait and it actually sounds like meatal on meatal. I have had a lot of automatic transmission befor and never have had this problem but it's good to know it is not just mine

Well, I don't get any sounds at all, so I'd say you have a problem. In mine, it feels like the transmission is in neutral, then finally engages and off we go. I chalk it up to another case of the truck doing what it wants, and not what I tell it to do.

Rme2513 · May 27, 2015

Well mine will do that also if I don't wait long enough if I'm in a hurry it just slips if I wait but not long enough it will lunge like you are talking about and I have already had my transmission replaced threw GM while this one is noise free it still dose what we have been talking about

Higgs Boson · May 27, 2015

The torque management will control the shift into gear and controls each shift gear to gear. It's not mechanical, it is too smart to let it go into gear before fluid and pressure is correct.

That's not to say the cold temp torque management is perfect because it is not. The tall first gear, 4.56, means it is a long way to second and the first shift of the delay is always slow and awkward. After that, it's nice.

Rme2513 · May 27, 2015

The torque management will control the shift into gear and controls each shift gear to gear. It's not mechanical, it is too smart to let it go into gear before fluid and pressure is correct.

That's not to say the cold temp torque management is perfect because it is not. The tall first gear, 4.56, means it is a long way to second and the first shift of the delay is always slow and awkward. After that, it's nice.

Are you seriously blaming that on the gear ratio you do know there are on 4 gears in this transmission and that they use two gears to make up the 8 gear ratios don't you and if it's so smart why can I feel it go in to gear and then still slip I'm sure you are proud of yours but my 09 6l80 was 10 times better then this hunk of junk and by the way the 6l80 first gear is 4.027 and second is 2.364 that is a diffeance of 1.663 and the 8l90 is a iffeance of 1.59 so of if your way of thinking were right your still wrong

CptMcSaug · May 27, 2015

^^ Holy crap? Calm your panties buddy.

But I don't have an issues with mine. But I don't turn the key and go to drive. I normally remote start mine then get in, seat belt and get settled.

Also,

"Gear ratios are 4.56:1 (1st), 2.97:1 (2nd), 2.08:1 (3rd), 1.69:1 (4th), 1.27:1 (5th), 1.00:1 (6th), 0.85:1 (7th), 0.65:1 (8th) and 3.82:1 (Reverse)."

http://news.pickuptrucks.com/2014/08/gm-stuffs-hydra-matic-8l90-with-technology.html

Rme2513 · May 27, 2015

^^ Holy crap? Calm your panties buddy.

But I don't have an issues with mine. But I don't turn the key and go to drive. I normally remote start mine then get in, seat belt and get settled.

Also,

"Gear ratios are 4.56:1 (1st), 2.97:1 (2nd), 2.08:1 (3rd), 1.69:1 (4th), 1.27:1 (5th), 1.00:1 (6th), 0.85:1 (7th), 0.65:1 (8th) and 3.82:1 (Reverse)."

http://news.pickuptrucks.com/2014/08/gm-stuffs-hydra-matic-8l90-with-technology.html

I have never had to wait after I crank up my truck or car and put it in gear for the transmission to prime up why should I have to on this new 50k$ truck. If you all only knew the trouble I have had with this truck and the only reason I still have it is because Im not going to take a 10k$ hit on it to trade it in

Higgs Boson · May 27, 2015

Are you seriously blaming that on the gear ratio you do know there are on 4 gears in this transmission and that they use two gears to make up the 8 gear ratios don't you and if it's so smart why can I feel it go in to gear and then still slip I'm sure you are proud of yours but my 09 6l80 was 10 times better then this hunk of junk and by the way the 6l80 first gear is 4.027 and second is 2.364 that is a diffeance of 1.663 and the 8l90 is a iffeance of 1.59 so of if your way of thinking were right your still wrong

Oh i see you don't want help, you just want a shoulder to cry on. Ok go ahead, cry it out.

by the way, my actual sentences blame it on poor cold torque management programming, not the gear ratio. after you dry your eyes you should read it again and come back and apologize for your tantrum.