[DarkMaroSS]

I understand just like many this is an old post, but I had my flush supposedly done by the dealer around 10-15k miles and all was well until now that it has 31,600 miles on it and no warranty as it is past the 5yr/60k miles powertrain warranty. It is a 2018 Camaro SS. What advice if any would guys give?

[ctrlz]

Originally Posted by DarkMaroSS

It is a 2018 Camaro SS. What advice if any would guys give?

You are going to need to price out torque converter replacement. Maybe the dealer will work with you.

The whole idea of the fluid flush fixing this problem was very dependent on how much uneven wear had already occurred to cause the "shudder." Without question it was cheaper for GM to offer the flush (or multiple flushes) compared to replacing the torque converter. Pray that the customer drives off and has no trouble until out of warranty.

[DarkMaroSS]

Originally Posted by ctrlz

…Pray that the customer drives off and has no trouble until out of warranty.

You said right! The bandaid approach is so it holds until out of warranty to get people come back and spend money.

[cengell]

Hi all, got a 2017 Camaro Convt, and Friday after been driving for 6 hours hwy driving and in cruse control in 8th (A8 transmission) gear at 55 MPH on a somewhat level road and saw the Tac moving up then down at 1500/2000 RPM range.

I did feel the car was surging and turned off the cruse and kept as about the same RPM I felt the same.

I am aware of the reported Fluid replacement as a temp fix for some have had done.
1 thing I do is downshift with the paddles to save some wear on the brakes, and maybe this could contribute to the surging/shuttering in the torque converter?

I am now just over 60K but have the GMPP good until 9/28/2024 or 78K, so i'm under that.

I want to do my research before I take it to my GM dealership. I was told to take to a Cadillac dealership over a GM, thinking better support over the GM dealership?

If there is any newer info, please post links..

Thank you!
Christopher

[arpad_m]

Originally Posted by cengell

Hi all, got a 2017 Camaro Convt, and Friday after been driving for 6 hours hwy driving and in cruse control in 8th (A8 transmission) gear at 55 MPH on a somewhat level road and saw the Tac moving up then down at 1500/2000 RPM range.

I did feel the car was surging and turned off the cruse and kept as about the same RPM I felt the same.

I am aware of the reported Fluid replacement as a temp fix for some have had done.
1 thing I do is downshift with the paddles to save some wear on the brakes, and maybe this could contribute to the surging/shuttering in the torque converter?

I am now just over 60K but have the GMPP good until 9/28/2024 or 78K, so i'm under that.

I want to do my research before I take it to my GM dealership. I was told to take to a Cadillac dealership over a GM, thinking better support over the GM dealership?

If there is any newer info, please post links..

Thank you!
Christopher

Hi Christopher, the fluid exchange is not a bandaid or a "temp fix" as many claim but the proper solution, provided the TCC (torque converter clutch) friction material hasn't yet degraded beyond a certain point. After that, a torque converter replacement and using the correct fluid to refill is the proper solution.

GM introduced clutch pressure modulation based artificial slip into the transmission tune for the 8L45 and the 8L90, which supposedly improves fuel economy a tiny bit, but depends heavily on the friction coefficient of the transmission fluid. Even a small amount of water absorption reduces this coefficient enough to lead to a continuous slip-grap-slip-grab condition in specific gear/rpm/slip ranges that the driver perceives as "shudder", which gets stronger over time and "creeps" into other gears and rpms as the TCC friction material gradually abrades. The latest Mobil 1 Synthetic LV ATF HP transmission fluid (part number 19417577) is much less hygroscopic than any of the older fluids, so it does not suffer from this problem.

This is also why
1) fluid quality in terms of friction properties is definitely very important in the 8L45/8L90, it isn't the old days of simple slush boxes anymore,
2) the shudder condition depends on moisture content in the air, so it may never (or much, much later) surface in drier climates but may occur very soon and easily in humid states; after all, the tramission and its cooler assembly with the lines isn't a 100% airtight system
3) downshifting doesn't prevent the issue, you just shift out of the "problem zone" for the time being, but over time the trans will start shuddering in 7th gear, too
4) many tune out the programmed slip to say goodbye to this problem for good, but of course that also says goodbye to any powertrain warranty.

I'd visit the dealership ASAP and not try the fluid exchange in my garage, because a proper flush requires their professional equipment. Even if a new torque converter is required, fortunately you still have warranty, so I suggest that you drive 200-250 miles on the new fluid, then if the shudder returns or remains, insist on a TC replacement under warranty.