[Tex2SS]

Hey all,

Just heard back from the dealership concerning the transmission diagnostics that they performed on my 2016 Camaro 2SS Vert today.

They are recommending a full transmission replacement to the tune of $9,343.24 because they found it to have delayed engagement, harsh shifts, and transmission shuddering. The exact things that GM is being sued about over and over again.

Anyway... Have any of you decided to go 3rd party and replace this POS with a different transmission altogether or perhaps you had someone just replace the Torque Converter with an aftermarket part?

I am currently at 36K miles and I am afraid to even drive this thing on the highway since the shudder is so bad. I had the triple flush done at 1K miles, but it obviously did not fix anything.

I've read through a ton of threads about this issue on here, but most of them say to get the flush and then all is good. I can not seem to find anyone in the threads talking about what they did to replace or repair their transmission when the flush failed them like it did me.

Thanks!

[Joshinator99]

Originally Posted by Tex2SS

Hey all,

Just heard back from the dealership concerning the transmission diagnostics that they performed on my 2016 Camaro 2SS Vert today.

They are recommending a full transmission replacement to the tune of $9,343.24 because they found it to have delayed engagement, harsh shifts, and transmission shuddering. The exact things that GM is being sued about over and over again.

Anyway... Have any of you decided to go 3rd party and replace this POS with a different transmission altogether or perhaps you had someone just replace the Torque Converter with an aftermarket part?

I am currently at 36K miles and I am afraid to even drive this thing on the highway since the shudder is so bad. I had the triple flush done at 1K miles, but it obviously did not fix anything.

I've read through a ton of threads about this issue on here, but most of them say to get the flush and then all is good. I can not seem to find anyone in the threads talking about what they did to replace or repair their transmission when the flush failed them like it did me.

Thanks!

If the triple flush didn’t fix it then I’d probably go for a new OEM converter. The shudder damages the torque converter clutches internally so not resolving the shudder right away smokes the converter.

FYI bought my ‘17 new and zeroed out the TCC slip tables right away and never had a shudder issue.

[arpad_m]

I'm not seeing why the entire transmission would need to be replaced unless they took it apart and found significant physical damage. I would bet they did none of that.

A torque converter ($350), new fluid ($150-200) and a day or two of labor to pull the transmission and replace the TC is all that should be needed.

I know this isn't your fault per se, it shouldn't be your job to stay up to date on GM powertain flaws and their remedies. However, there is no denying that if the trans has been shuddering for a long time, being a 2016 from 8 years ago after all, this is unfortunately expected and could've been prevented by flushing with the correct Mobil1 fluid that has been available since Jan 2019.


The 8L90 is a very good transmission, far from a POS. Following their usual corporate penny-pinching strategy, GM was unable (perhaps unwilling) to dedicate significant resources to finding the cause of the shudder, which was the hygroscopic nature of their early transmission fluids.

[KingLT1]

The 8l90 is a solid transmission. Unfortunately, most of the issues are based around the torque converter. The torque converter isn't the transmission. But even then, the issue isn't really the torque converter. It's a combination of incorrect fluid and tuning. GM engineers decided they wanted the transmission to slip in and out of AFM mode so you don't feel it like you could on the A6 in the 5th Camaro. It also helps make power down shifts smoother. Either way it's hard on the converter clutches and the original fluid used would cause the clutches to chatter and you get the shudder and erratic shifting behavior because the transmission locks and unlocks on gear changes.

Before spending thousands, I would pay for a triple flush and have the adaptives reset first. Then reach out to a performance shop and have the transmission tuned. I could do it for you remotely if you had HPtuners.

[dmcmahan60]

Pray Performance has a transmission guy that builds the 8 speed auto's to handle mad power. If you are interested in going this route. I would do what was said above first. I have had mine flushed at 21k then at 60k to have a temp sensor cable replaced. I am at 142k now with no issues

[Chutzpah]

If I may add to the others in saying, get it flushed again. It may have been flushed with the original and “faulty” fluid, as opposed to the reformulated version.

I’d go to a different shop or dealer and request the above. Replacing the entire transmission doesn’t make sense.

[Tex2SS]

It's interesting that you mention the AFM mode. I saw several posts a while back that mentioned that some people with the shudder were retuning their cars to get rid of this feature or just switching to manual mode, shifting from 8th to 7th and then back to 8th. I do notice a significant decrease in the shuddering when I do this manual shifting trick.

Originally Posted by KingLT1

The 8l90 is a solid transmission. Unfortunately, most of the issues are based around the torque converter. The torque converter isn't the transmission. But even then, the issue isn't really the torque converter. It's a combination of incorrect fluid and tuning. GM engineers decided they wanted the transmission to slip in and out of AFM mode so you don't feel it like you could on the A6 in the 5th Camaro. It also helps make power down shifts smoother. Either way it's hard on the converter clutches and the original fluid used would cause the clutches to chatter and you get the shudder and erratic shifting behavior because the transmission locks and unlocks on gear changes.

Before spending thousands, I would pay for a triple flush and have the adaptives reset first. Then reach out to a performance shop and have the transmission tuned. I could do it for you remotely if you had HPtuners.

[Tex2SS]

Originally Posted by Chutzpah

If I may add to the others in saying, get it flushed again. It may have been flushed with the original and “faulty” fluid, as opposed to the reformulated version.

I’d go to a different shop or dealer and request the above. Replacing the entire transmission doesn’t make sense.

I had the 18-NA-355 triple flush service performed with the new fluid in April of 2019 when the car only had 1,653 miles on it.

I definitely need to find someone around the DFW area to take this thing to, but I really want to find someone that knows all of the things that you have all mentioned... The correct TC to use, the adaptive reset (whatever that is Lol), the AFM module issues, the right fluid, etc.

[rcoe]

Originally Posted by Tex2SS

I had the 18-NA-355 triple flush service performed with the new fluid in April of 2019 when the car only had 1,653 miles on it.

I definitely need to find someone around the DFW area to take this thing to, but I really want to find someone that knows all of the things that you have all mentioned... The correct TC to use, the adaptive reset (whatever that is Lol), the AFM module issues, the right fluid, etc.

Circle D in Houston can build you a nice 8L90 with converter. Not sure if they work on cars or just build the transmissions. But my stage 3 has held up to some abuse.

[Tex2SS]

Thanks.

I just watched a video of someone getting a Circle D Torque Converter installed. I did not realize that they were in Houston.

I'll reach out to them to see what their suggestions are for my car.

Originally Posted by rcoe

Circle D in Houston can build you a nice 8L90 with converter. Not sure if they work on cars or just build the transmissions. But my stage 3 has held up to some abuse.

[Tex2SS]

Thanks for the response.

Neither of the dealers have ever mentioned the AFM to me in all the years that I have been bringing this car to them complaining about the shudder. It wasn't until I read a post on here recently about using manual mode to disable it and it definitely makes an improvement on the highway.

I went ahead and ordered a Range AFM/DFM disabler (Part# RA003B) and it will be here tomorrow.

I do have a few questions if you don't mind:
1. What do you mean by having the adaptives reset? Is this like disconnecting the battery to reset the learned driving patterns?
2. Tuning the transmission. What does the tuning do for me or what is it that needs to be reconfigured? Is this an ECU change that we are talking about?
3. I had the triple flush with the new fluid at about 1,600 miles. Should I do it again? I am currently at about 38K miles.

Originally Posted by KingLT1

The 8l90 is a solid transmission. Unfortunately, most of the issues are based around the torque converter. The torque converter isn't the transmission. But even then, the issue isn't really the torque converter. It's a combination of incorrect fluid and tuning. GM engineers decided they wanted the transmission to slip in and out of AFM mode so you don't feel it like you could on the A6 in the 5th Camaro. It also helps make power down shifts smoother. Either way it's hard on the converter clutches and the original fluid used would cause the clutches to chatter and you get the shudder and erratic shifting behavior because the transmission locks and unlocks on gear changes.

Before spending thousands, I would pay for a triple flush and have the adaptives reset first. Then reach out to a performance shop and heav the transmission tuned. I could do it for you remotely if you had HPtuners.

[rcoe]

Originally Posted by Tex2SS

Thanks.

I just watched a video of someone getting a Circle D Torque Converter installed. I did not realize that they were in Houston.

I'll reach out to them to see what their suggestions are for my car.

There are 2 of them in Houston. Circle D converters and Circle D transmission. They are not the same shop but work with each other.

[Tex2SS]

Thanks.

I sent the following email out to both Circle D Specialties and Circle D Transmissions as well as BRC Raceworks (used to be Cunningham Motorsports).

Hey guys,

2016 SS Camaro owner here with the good ole shuddering and slipping 8L90 torque converter issue. Wanted to see what you guys usually recommend for this and what the damage would be to have you repair it.

Some notes:
Triple flush and pan clean was done at 1,600 miles. [TSB 18-NA-355]
Currently at 38K miles.
No Mods
Daily Driver

Been reading up in the Camaro6 forums about what everyone is trying and I am seeing a lot of varied answers and solutions that sometimes work and sometimes not. Have you been able to resolve this for folks? If so, was it just a TC replacement (OEM or 3rd Party?) and retune or does it require more? I just bought a Range AFM/DMF disabler to at least minimize the highway shuddering for now.

Thanks,
-Frustrated GM Owner

Originally Posted by rcoe

There are 2 of them in Houston. Circle D converters and Circle D transmission. They are not the same shop but work with each other.

[KingLT1]

Originally Posted by Tex2SS

It's interesting that you mention the AFM mode. I saw several posts a while back that mentioned that some people with the shudder were retuning their cars to get rid of this feature or just switching to manual mode, shifting from 8th to 7th and then back to 8th. I do notice a significant decrease in the shuddering when I do this manual shifting trick.

Thanks for the response.

Neither of the dealers have ever mentioned the AFM to me in all the years that I have been bringing this car to them complaining about the shudder. It wasn't until I read a post on here recently about using manual mode to disable it and it definitely makes an improvement on the highway.

I went ahead and ordered a Range AFM/DFM disabler (Part# RA003B) and it will be here tomorrow.

I do have a few questions if you don't mind:
1. What do you mean by having the adaptives reset? Is this like disconnecting the battery to reset the learned driving patterns?
2. Tuning the transmission. What does the tuning do for me or what is it that needs to be reconfigured? Is this an ECU change that we are talking about?
3. I had the triple flush with the new fluid at about 1,600 miles. Should I do it again? I am currently at about 38K miles.

That's what starts it. Also, the converter being locked part throttle doesn't help. Imo the lock up clutch isn't nearly as robust as a good aftermarket converter like Circle D. So I run the converter unlocked part throttle in all gears until 8th @ 55-60 mph. You lose like 1 mpg at best. The converter is tight enough that it actually drives and shifts better this way imo. Gm only does any of this crap for fuel mileage...

1) Fast learn reset for the TCM resets all the learning adaptives. The TCM adjusts based on driving characteristics.

2) Tuning fixes all the crap GM did to improve fuel economy a measly 1mpg at the expense of longevity and drivability. Unfortunately, they had to do this crap to get these V8's to meet regulations.

3) Yes, the fluid needs changed more often since it's programmed to slip 10% as it transitions in/out of lock up and AFM mode. If you tune all of this out then you won't need to change the fluid as much. With stock tuning I would change fluid every 25k miles.