Frustrated with GM and this Transmission!!!

elementaltoad · July 19, 2017

I have a 2017 CCSB 5.3/6speed 4x4, with a little over 400 miles on mine and I am starting to notice some strange shifting issues. It didn't do this on the test drive or the drive home, but it was all highway back.

Now that we are home with it, it is mostly 45-60mph around town. I definitely notice it more from stops or slowing to let a car turn, then trying to accelerate again, or while turning then accelerating from a slow roll. The transmission seems to stick in a higher gear, and jerks back and forth gently while accelerating, which can be seen on the tach bouncing around, almost like it is lugging or missing. It reminds me of my old LS1 with a bad plug wire, or a slipping gear when it just sits at 3k RPM or so going no where on a downshift. From a dead stop at a light, or making a right turn into traffic the thing is dog slow if you give it less than ~50% throttle, any more than that and it downshifts a bunch of gears at once it feels like and hits 4k+ RPM. I'm usually the slowest guy off the light and I'm hard pressed to catch back up with traffic unless I throttle it hard. I also started noticing a "thump" coming out of v4 mode trying to accelerate on the highway.

I'll be seeing if they have an update for the trans calibration as said when I go in for the first oil change, so I can give it a chance to level out before then. I love the truck otherwise, and I'm extremely familiar with LS architecture and GM transmissions. This thing definitely needs a tune it feels like, but for what we pay for these trucks, it should at least feel solid from the factory without making me wonder if the clutch packs are slipping or the torque converter is locking and unlocking repeatedly.

mookdoc6 · July 19, 2017

I have a 2017 CCSB 5.3/6speed 4x4, with a little over 400 miles on mine and I am starting to notice some strange shifting issues. It didn't do this on the test drive or the drive home, but it was all highway back.

Now that we are home with it, it is mostly 45-60mph around town. I definitely notice it more from stops or slowing to let a car turn, then trying to accelerate again, or while turning then accelerating from a slow roll. The transmission seems to stick in a higher gear, and jerks back and forth gently while accelerating, which can be seen on the tach bouncing around, almost like it is lugging or missing. It reminds me of my old LS1 with a bad plug wire, or a slipping gear when it just sits at 3k RPM or so going no where on a downshift. From a dead stop at a light, or making a right turn into traffic the thing is dog slow if you give it less than ~50% throttle, any more than that and it downshifts a bunch of gears at once it feels like and hits 4k+ RPM. I'm usually the slowest guy off the light and I'm hard pressed to catch back up with traffic unless I throttle it hard. I also started noticing a "thump" coming out of v4 mode trying to accelerate on the highway.

I'll be seeing if they have an update for the trans calibration as said when I go in for the first oil change, so I can give it a chance to level out before then. I love the truck otherwise, and I'm extremely familiar with LS architecture and GM transmissions. This thing definitely needs a tune it feels like, but for what we pay for these trucks, it should at least feel solid from the factory without making me wonder if the clutch packs are slipping or the torque converter is locking and unlocking repeatedly.

They are awful from the get-go and take 1000's of miles unfortunately.....It will be a distant memory hang in there!

elementaltoad · July 19, 2017

They are awful from the get-go and take 1000's of miles unfortunately.....It will be a distant memory hang in there!

I have no choice, I want to keep the warranty, and I wouldn't bail for a Ford or Dodge anyway. But I also have HPTuners sitting right here on this laptop....like an itch I can't scratch

Gotsumpnferya · August 1, 2017

Anybody find it unacceptable that you spend a ton of your hard earned money on a vehicle that needs a "special" tune in order for it act the way it should? Some serious brand loyalty going on I guess!

Yeah , but that's just how it goes . I don't think I've owned any vehicle where I was 100% happy with it the way it was from the factory but then found a way to make it better .

ram1067 · August 3, 2017

I have a 2017 CCSB 5.3/6speed 4x4, with a little over 400 miles on mine and I am starting to notice some strange shifting issues. It didn't do this on the test drive or the drive home, but it was all highway back.

Now that we are home with it, it is mostly 45-60mph around town. I definitely notice it more from stops or slowing to let a car turn, then trying to accelerate again, or while turning then accelerating from a slow roll. The transmission seems to stick in a higher gear, and jerks back and forth gently while accelerating, which can be seen on the tach bouncing around, almost like it is lugging or missing. It reminds me of my old LS1 with a bad plug wire, or a slipping gear when it just sits at 3k RPM or so going no where on a downshift. From a dead stop at a light, or making a right turn into traffic the thing is dog slow if you give it less than ~50% throttle, any more than that and it downshifts a bunch of gears at once it feels like and hits 4k+ RPM. I'm usually the slowest guy off the light and I'm hard pressed to catch back up with traffic unless I throttle it hard. I also started noticing a "thump" coming out of v4 mode trying to accelerate on the highway.

I'll be seeing if they have an update for the trans calibration as said when I go in for the first oil change, so I can give it a chance to level out before then. I love the truck otherwise, and I'm extremely familiar with LS architecture and GM transmissions. This thing definitely needs a tune it feels like, but for what we pay for these trucks, it should at least feel solid from the factory without making me wonder if the clutch packs are slipping or the torque converter is locking and unlocking repeatedly.

X2...... 2017 DBC 5.3 1200k at least the damn thing does grown like a goose when turning left, like my 06 CC and many others! GM never addressed that issue!

elementaltoad · August 3, 2017

X2...... 2017 DBC 5.3 1200k at least the damn thing does grown like a goose when turning left, like my 06 CC and many others! GM never addressed that issue!

Mine is going to the shop today, shifting is just getting worse, it will bounce you back and forth pretty hard sometimes trying to accelerate from slow speeds. It really feels like a miss at low RPM. Both my girlfriend and my dad who have driven it hate it, and I've noticed a rough idle/idle dip that nearly stalled the truck a couple of times.

elementaltoad · August 3, 2017

I just got back from the dealer, and there was in fact a programming update for the transmission missing from mine. The service manager just sighed and hung his head when I first came in. I explained the odd shifting and asked about the idle dip issue "Yeah you can blame the EPA for that, it's completely normal". I took a tech for a drive and he asked if I had the "Chevy Shake", which I haven't had an issue with, but I did show them the lug/bog from the trans holding gears or lockup at low speeds. They flashed a new update to the trans, which is 24288803 "calibration to correct chuggle", it instantly felt better leaving the dealer, it holds a lower gear in the parking lot or slow driving rather than trying to lug around. It also downshifts with much less throttle input it feels like. I still have a bit or jerking at low speed turns around 1-1.5k RPM. I'm hoping that will smooth out, but it is not as bad as it was.

Pacfanweb · August 5, 2017

Anybody find it unacceptable that you spend a ton of your hard earned money on a vehicle that needs a "special" tune in order for it act the way it should? Some serious brand loyalty going on I guess!

It kind of is, but the alternative (Ford, Dodge) isn't any better (and in fact might be worse) so it's not just "brand loyalty".