subfloor@centurytrans

2015 Z06, just under 15K miles.

Driving home from work on Monday night I noticed after making a right turn at a stoplight the engine RPM started shooting up and I quickly lost all forward movement (as well as reverse).

After sitting for several minutes and getting ready to call AAA to have it towed, for some reason I thought what the heck and started it up again to see if I could make it to the dealership since they were literally around the corner from where I broke down.

Oddly enough the car felt fine and I was able to make it about a 1/4 mile before it happened again. I waited another couple of minutes and was able to finally make it there, although I was coasting at the very end.

The dealership hasn't torn it down yet but in the meantime I was curious if this same (or similar) thing has happened to anybody else. Basically it'll drive fine for a VERY short distance before not moving at all.

No codes were thrown and I didn't see any leaking fluid underneath.

Flame Red

Yeah, that is something new. Never heard of that sort of failure before.

Might be a computer issue. My A8 was replaced with 100 miles on the clock. Mine would still move a little, never stuck. But mine too would act ok on restart. Turned out it was the TCM. At the time, the A8 was brand new and they did not permit dealer techs to open the A8, so they swapped the whole bloody thing even though the TCM is external. I also had codes, and backfiring. But it acted normal for a while after restart just like yours.

Not So Fast

I have been following the thread about the A-8 tranny because that's what I would want if/when I trade up, but after reading all of these kind of problems I think I'll pass, my A-6 works great
Hope they get it figured out permanently so that you don't have the "intermittent" ordeal to go thru
NSF

subfloor@centurytrans

Turns out that some (but not all) of the clutches burned up due to a lack of proper fluid pressure.

When the tech contacted GM support they had apparently seen it happen a few times before, so the shop rebuilt it and should have it finished for me today. They ended up replacing the bad clutches and installed a brand new housing due to a possible defect which they suspect might have caused the pressure issue.

PobreWey

always an A8 with issues here. Never any with the m7. GM needs to get their act together.

Rebel Yell

I glad to hear you got your baby fixed my friend.

Hopefully (but not holding my breath) GM can find a way to use the A10 (that was a joint venture with Ford) in the Corvette someday. After reading some reviews, and watching videos of the A10 in the '18 Mustangs I was quite impressed. If they can't figure a way, they do as you say get their act together. My A8 (with 7500 miles) has been fine, but has it's quirks, and one never knows if that slush box will last.

onyx_z71

Although this is not a typical A8 failure, I believe it happened for the same reason as the torque converter issues. I think it's the low pressure pump in the valve body not being up to task.

The A8 low pressure pump feature is primarily what makes the transmission more fuel efficient then the A6 because it greatly reduces parasitic loss of running full hydraulic pressure during light load/cruising. This would also explain why there may be less issues with cars driven in paddle mode as the pump probably stays at high pressure during that time.

rmorin1249

I experienced a similar issue about a week ago. I was slowing down to make a right turn and when I began to accelerate after making the turn the engine revved up but the car was not accelerating. I let off the gas and all went back to normal. The rear tires were not spinning, road was dry and I was only very lightly accelerating. Hasn't happened again but I continue to worry about the longterm reliability of the drive train in my car. Glad I have a GMEPP for 7 years. I will dump the car before it expires.