Who likes their 8 Speed?

[muhsfink07]

imagine a rough road/ rumble strip/ surging/ misfiring feeling that goes away when you back off of the gas. thats my impression anyway

[foghorn23]

I have had the downshift clunk one time. It has had 4 or 5 episodes where it didn't downshift all the way to first at a stop sign. Pulling out in traffic as such is an adventure. Anyway I started manually downshifting to low for a few days on my normal route and the smart tranny seems to have learned its lesson. No issues lately. Smooth as silk on the road though...thank goodness.

[jetfixer737]

Mine has been to 2 different dealerships in 2 different states 6+ times and has received at least 13 software updates. Like most others it suffered from hard 1-2 up shifts (Clunks) and occasional HARD 2-1 down shifts. At present the 1-2 shift issue seems to be better (softer) and some days perfect. The 2-1 down shift issue seems to be cured.

However...

Nowadays at slow speeds such as on tight neighborhood streets, and in shopping center parking lots it now clunks, slips, & flares in totally random combinations, gears and times. Drive this thing "like ya stole it" and it's wonderful, but if I drive it like a civilized human being and try to save a few drops of gas it punishes me for trying.

 

I plan on being rid of it by the end of the year.

 

FYI: Obviously this is a known issue, but apparently more of an issue in the 6.2/8 speed combination. In fact during my last visit to the local Chevy dealer I spoke to the general manager who told me "We won't stock the 6.2 powered Silverados here. Only the 5.3's. If somebody really wants one, we'll get them one, but because of all the transmission issues we do not, and will not keep any 6.2 1500's in our inventory."

Edited March 21, 2017 by jetfixer737

[Snoringbear]

Mine has been to 2 different dealerships in 2 different states 6+ times and has received at least 13 software updates. Like most others it suffered from hard 1-2 up shifts (Clunks) and occasional HARD 2-1 down shifts. At present the 1-2 shift issue seems to be better (softer) and some days perfect. The 2-1 down shift issue seems to be cured.

However...

Nowadays at slow speeds such as on tight neighborhood streets, and in shopping center parking lots it now clunks, slips, & flares in totally random combinations, gears and times. Drive this thing "like ya stole it" and it's wonderful, but if I drive it like a civilized human being and try to save a few drops of gas it punishes me for trying.

 

I plan on being rid of it by the end of the year.

 

FYI: Obviously this is a known issue, but apparently more of an issue in the 6.2/8 speed combination. In fact during my last visit to the local Chevy dealer I spoke to the general manager who told me "We won't stock the 6.2 powered Silverados here. Only the 5.3's. If somebody really wants one, we'll get them one, but because of all the transmission issues we do not, and will not keep any 6.2 1500's in our inventory."

Agree with your " Drive this thing "like ya stole it" and it's wonderful" comment. I've had my 8 spd reprogrammed twice but still experience the low end up/down shifting problem occasionally, usually in the first drive of the day and especially if just poking along. My cure for this is to just stomp the piss out of the gas pedal and run the tranny through the gears with the throttle full bore wide open. Seems to behave for the rest if the day when I do this. Gotta say though, I bought the 6.2/8spd combo for towing my 6,000 lb TT and love it for this. So, I'm willing to live with occasional bad behavior when driving with no load. It's like a spirited horse, gotta put the spurs to it and run it hard first thing in the morning

[bosro]

Agree with your " Drive this thing "like ya stole it" and it's wonderful" comment. I've had my 8 spd reprogrammed twice but still experience the low end up/down shifting problem occasionally, usually in the first drive of the day and especially if just poking along. My cure for this is to just stomp the piss out of the gas pedal and run the tranny through the gears with the throttle full bore wide open. Seems to behave for the rest if the day when I do this. Gotta say though, I bought the 6.2/8spd combo for towing my 6,000 lb TT and love it for this. So, I'm willing to live with occasional bad behavior when driving with no load. It's like a spirited horse, gotta put the spurs to it and run it hard first thing in the morning

I thought I was crazy....

Couple weeks ago my truck tranny was doing all the bad things

I got pissed and decided to go to manual and shift the damn thing....and drive the shit out of it☺

For lack of a better term was "aggressively" shifting up and down in manual....I literally didn't care if something broke.

I sort of got sick of doing this after several days tho.

But crazy enough now the tranny is not doing the bad things...or hardly is

I continue to go to manual and do some aggressive shifting occasionally but I now don't feel like getting rid of the truck...

I don't understand it ....but I don't understand a lot of things

[Snoringbear]

I thought I was crazy....

Couple weeks ago my truck tranny was doing all the bad things

I got pissed and decided to go to manual and shift the damn thing....and drive the shit out of it☺

For lack of a better term was "aggressively" shifting up and down in manual....I literally didn't care if something broke.

I sort of got sick of doing this after several days tho.

But crazy enough now the tranny is not doing the bad things...or hardly is

I continue to go to manual and do some aggressive shifting occasionally but I now don't feel like getting rid of the truck...

I don't understand it ....but I don't understand a lot of things

Lol, understand. Lots of things I don't understand either, especially women. And, I'm married with three adult daughters and a female dog. But, I degress. I'm thinking, with zero empirical data to back this, that part of the problem with the 8 spd is that it's an 8 spd, thus the programming becomes confused at times which gear it's supposed to be in. I don't know how well the new 10 spd Ford/GM tranny is performing as I haven't done any research on it. But, I wouldn't be surprised if it should have similar problems such as searching for correct gear. I think as some point the law of diminishing returns (showing off my freshman Econ:) ) will come into play pretty soon. I don't see much value above 10 gears. Maybe it's time to put some serious money into some sort of constant velocity tranny that would be stout enough for truck use. Anyway, my thumbs are getting tired. So, calf rope, I'm through

[mookdoc6]

Lol, understand. Lots of things I don't understand either, especially women. And, I'm married with three adult daughters and a female dog. But, I degress. I'm thinking, with zero empirical data to back this, that part of the problem with the 8 spd is that it's an 8 spd, thus the programming becomes confused at times which gear it's supposed to be in. I don't know how well the new 10 spd Ford/GM tranny is performing as I haven't done any research on it. But, I wouldn't be surprised if it should have similar problems such as searching for correct gear. I think as some point the law of diminishing returns (showing off my freshman Econ:) ) will come into play pretty soon. I don't see much value above 10 gears. Maybe it's time to put some serious money into some sort of constant velocity tranny that would be stout enough for truck use. Anyway, my thumbs are getting tired. So, calf rope, I'm through

Agreed, GM has publicly stated that going above 10Speeds is not going to happen as the efficiency returned on investment would never happen. Look at FERD'S 10speed it netted 1mpg better on the HWY? For Public relations aspects nobody says anything? If GM announced it they would be laughed at of course! Anyway, Properly spaced 7-8speed is ample! The 8L90 has issues in trucks because it's input is off like 200HP/Tourque! It's massively Torque hungry and instantly needed.....I suspect the problems are fluid/pressure related and not enough. GM had the fluid updated to HP which is supposed to have way better cold performance! Not the case it seems with what people are reporting.......So I go back to pressures as being the problem? Who knows the harder you hammer the gears the better it runs? I totally get it because I have one and the love/hate relationship.

Edited March 24, 2017 by mookdoc6

[dasimmon]

sounds like the 8 speed is about as popular as the 6...some love it, some hate it

[mookdoc6]

I can say, "I like the 8speed hands down over the 6speed"

[jetfixer737]

Agreed, GM has publicly stated that going above 10Speeds is not going to happen as the efficiency returned on investment would never happen. Look at FERD'S 10speed it netted 1mpg better on the HWY? For Public relations aspects nobody says anything? If GM announced it they would be laughed at of course! Anyway, Properly spaced 7-8speed is ample! The 8L90 has issues in trucks because it's input is off like 200HP/Tourque! It's massively Torque hungry and instantly needed.....I suspect the problems are fluid/pressure related and not enough. GM had the fluid updated to HP which is supposed to have way better cold performance! Not the case it seems with what people are reporting.......So I go back to pressures as being the problem? Who knows the harder you hammer the gears the better it runs? I totally get it because I have one and the love/hate relationship.

 

...And yet "FERDS" 10 speed WILL be in GM trucks, probably beginning with the 2018 model year. (Called the 10Lxx) But that's not all, some may recall Ford/GM also went in together on a 6 speed front drive transmission (6T70/6T75) and at first it was dreadful. The GM version was blowing up left & right. I had one in a 2008 Saturn (Malibu) and it was SO bad GM finally had to step up and give the early ones a 10 year/120,000 mile warranty. After they corrected the known weak link (called a 3,5 reverse wave plate) the 6 speed was excellent, and yet they've now re-engineered that transmission into the 9T40 nine speed, and it's already out in some GM products. (The 2018 Terrain gets it) We'll see...

[mookdoc6]

 

...And yet "FERDS" 10 speed WILL be in GM trucks, probably beginning with the 2018 model year. (Called the 10Lxx) But that's not all, some may recall Ford/GM also went in together on a 6 speed front drive transmission (6T70/6T75) and at first it was dreadful. The GM version was blowing up left & right. I had one in a 2008 Saturn (Malibu) and it was SO bad GM finally had to step up and give the early ones a 10 year/120,000 mile warranty. After they corrected the known weak link (called a 3,5 reverse wave plate) the 6 speed was excellent, and yet they've now re-engineered that transmission into the 9T40 nine speed, and it's already out in some GM products. (The 2018 Terrain gets it) We'll see...

 

I remember the 6speeds too and GM was given the head to market first on the Co-Develop......Hence your FERD boys get to market first with the Co-Developed 10speed! I owned a 2008 Malibu off the Lot brand new with the 6speed. It never blew up on me? Actually, It never failed either? Needed a Re-Flash......GM has never been the Auto manufacture of Bad Trans as far as I am concerned quite the opposite!

[Snoringbear]

Not to be out done ; I remember the day's of the two speed Powerglide. When the three speed Turbo-Hydromatic came on the scene everyone that that was the best thing since canned beer! To really stretch the old memory bank, had a good friend in high school who had a 1950 Desoto with Fluid Drive tranny; had standard three on the tree shifter and clutch. It could be shifted like any standard tranny of the day or it could be left in any gear of choice and ignore the clutch. In stop and go around town he would leave it in 2nd for ease of driving. It could take off from a dead stop in 3rd but would take an hour or so to get up to highway speed. I'm thinking the L Head in-line 6 had about 110hp. Anyway, always thought that it was an interesting first cut at an automatic tranny. Btw, that old four door Desoto was a great double-date car, especially being my date and I would have the back seat. Had WNOE big blaster putting out some good rock'n roll tunes. Dang it, digressed again! Sorry, lol

[jetfixer737]

Not to be out done ; I remember the day's of the two speed Powerglide. When the three speed Turbo-Hydromatic came on the scene everyone that that was the best thing since canned beer! To really stretch the old memory bank, had a good friend in high school who had a 1950 Desoto with Fluid Drive tranny; had standard three on the tree shifter and clutch. It could be shifted like any standard tranny of the day or it could be left in any gear of choice and ignore the clutch. In stop and go around town he would leave it in 2nd for ease of driving. It could take off from a dead stop in 3rd but would take an hour or so to get up to highway speed. I'm thinking the L Head in-line 6 had about 110hp. Anyway, always thought that it was an interesting first cut at an automatic tranny. Btw, that old four door Desoto was a great double-date car, especially being my date and I would have the back seat. Had WNOE big blaster putting out some good rock'n roll tunes. Dang it, digressed again! Sorry, lol

 

My first high school car (mom's car) was a 1969 Chevy Concours (Chevelle) station wagon with the 250/powerglide. Seemed like it would go as fast in reverse (Scary fast) as it would in drive. My dad always thought something was wrong with it since it only shifted once. That is, of course, until somebody explained to him what a powerglide was. He was used to Turbo-hydro 350's. In later years, on the weekends my buddies would insist I leave my Camaro at home and bring out the "party wagon" since it was inconspicuous. Wow, a flood of memories just hit me. Digressing must be contagious...

[CounterMeasure]

I wish GM would realize they can't design a transmission worth a damn, and just use the German ZF trannies. I understand they based the 8L90 off the ZF 8HP, thinking they could make it better, but they were dead wrong on that.

 

ZF's 6 speed in my wife's Hemi Charger, and their 8HP are a dream to drive. Smooth and predictable. In the 5 years we've owned the Charger, the transmission has never done a single thing that concerned me. No flares, no clunks, no bangs. My friends that have the 8 speed in their Hemi Rams love it, and I have to admit, when I've been in their trucks, I've listened hard for the tranny behavior. Never found anything that makes me think its "confused" or "sloppy". I'd kick a puppy if I could bolt one up to my 6.2L.

 

GM's 8L90 speed was designed during their bankruptcy panic and needing a bailout, and I think the product's performance shows...

 

I'd love to be a fly on the wall in the offices of the 8L90 team to see if the engineers think they did a wonderful job on it, or are ashamed to be associated with it. Based on my own career experiences, I would be willing to bet they know there are problems with it, and the hardware guys are blaming the software guys, and the software guys are blaming the hardware guys. Software is always used to patch hardware, because its cheaper.

[BobHancock]

My Grand Cherokee 8 speed is flawless. To get my truck to behave I use Tow/haul mode. Much better but not as good as the GC 8 speed.