Transmission shudder

[d1h]

Anyone have the transmission shudder issue on their Chevy Silverado with the 8 speed tranny? I think my 2018 has started doing it at cruising speed when going down the highway. Going to have to have it checked out. From what I've read about it a transmission fluid change usually solves the problem. Hope that's all it needs. I seen that there was a TSB issued for that problem.

[Grit_dog]

dodge guy wrote:
That’s normally a fluid change. Our Ram truck 8 speeds will hang up in 2nd gear when coming to a stop. Changing the fluid fixes the issue. Anyone that believes in lifetime fluids is asking for a large repair bill. The fluid is expensive, but it’s still cheaper than a trans.

Sorry for the off topic, but...
What are your real world thoughts on the preferred service (drain n fill or complete fluid replacement) on the 8HP70 behind a SRT8?
Car is 5 years old, approaching 40k miles, wife's summer driver, 99% commuter car, 1% husband done a few good burnouts and a couple top speed runs only.
Also is at absolutely necessary to replace the pan? I don't quite understand why that's a single use item.
I'm considering doing a service on it now around 40k miles since the car has been virtually flawless to date and plan is to keep it a long time.

[dodge_guy]

That’s normally a fluid change. Our Ram truck 8 speeds will hang up in 2nd gear when coming to a stop. Changing the fluid fixes the issue. Anyone that believes in lifetime fluids is asking for a large repair bill. The fluid is expensive, but it’s still cheaper than a trans.

[Campfire_Time]

Mine had 37k on when I bought it Jan. 2016 Silverado 5.3 with 8 speed. The previous owner had the flush done at 28k. I have 43k on it now. It's been very smooth. I've talked to a lot of people through forums and a few in person who have been very happy with their 8 speeds once the flush was done. And it tows wonderfully, not to mention really good day to day mileage.

There is quirkiness with AFM but I only see it at 45mph and under with a slight vibration. I learned to run in M7 when driving at 45mph or less. No vibration. Locking out AFM eliminates the V4 mode lag. And overall it's even smoother, I no long have wonky downshifts or slams in parking lots.

[d1h]

Only one reply out of over 350 who have read this post. Interesting, thought it was a more common issue. Anyway, I just had the flush and refill with the new Mobil 1 Synthetic and so far have not felt the shudder. Didn't cost anything to have it done at the dealer. Guy said to give it 500 miles worth of driving to give it time to circulate through the transmission really good. If for some reason it should come back he said torque converter replacement would be next step. Said 99 percent of the time flush and fill solves the problem.

[Retired_JSO]

It is probably caused by the trucks AFM ability when the truck switches to 4 cylinder mode. Several post concerning GM vehicles with AMF. Many forums reporting transmission shutter and lifter problems. The transmission TSB relating to fluid flush addresses what most report as when accelerating, feels like driving over rumble strips.

My 2019 Corvette has had both.