[LuvMyV6]

I took my 2017 V6 into the dealership for a transmission diagnostics. I had fingers crossed that I could get it serviced in time before it was completey done. Sure enough, the service department says I will need a whole new transmission. They're offering $7,700 for one of their brand new ones with a three year and 100,000 mile warranty. I can't afford that right now, and I'll have the car paid off in February.

My question is, how long has it been known for a transmission to last while shuddering? A few months? A year? Will it shudder forever? I'm working on getting a daily, which I was hoping to only do after paying off the car. This is also the 2nd transmission I've put into this car. Both around 60,000 miles and both outside of warranty.

[ramairroughneck]

The 8l90 in my truck was shuddering extremely bad at 70k. I changed the fluid in the pan. Drove around to get the fluid out of the converter, then changed the fluid and this time the filter, and it completely eliminated the shudder. Around 110k it started shuddering again and I repeated the process. Two fluid changes with the new filter on the second. I’m currently at 130k miles and it’s driving great. It’s definitely worth a try and whatever you do, do not have it flushed

[arpad_m]

The shudder is the torque converter clutch (TCC) engaging and disengaging in quick succession instead of completely locking up as instructed due to the accumulation of water and the resulting temporal and spatial friction coefficient variations in the transmission fluid. Over time, this erodes the wear material on the clutch and can have detrimental effects on the tranmission itself, although that latter effect I have not yet seen quantified and analyzed in depth.

First, I don't understand how exactly the dealership came to the conclusion that you need a $7,700 transmission instead of a $450 torque converter.

Second, I also don't understand what you are hoping to achieve by running the trans as long as possible with a known serious issue that has a well known and permanent fix. Was your car never given the flush with the proper Mobil1 LV fluid (released in Jan 2019) under TSB 18-NA-355? If not, why? This, coupled with a new torque converter fixes the problem for good, or at least for the entire useful life of the transmission.

[Hyperion]

Stealership BS don't fall for it bro. Get it flushed, you may not even have to replace the torque converter if it hasn't been shuddering long. Mine had the TSB flush done 40,000 miles ago and no issues since and all original.

[Megahurtz]

If the shudder issue isn't corrected in the first 500-1000 miles it risks damaging the Torque Converter to the point that a triple flush will not fix the issue. Then from that point it will just get worse. Regardless, 90% of the time a new converter, a triple flush and the latest ECU flash should fix the issue. I suppose its possible that it could eventually damage the transmission clutches but I've never heard of that being the case.

I'd be curious to know how the tech determined the Transmission was bad?

[jericho_17]

second transmission? if is the same dealer then you may consider getting a second opinion

[2SS Capt]

Originally Posted by Megahurtz

I'd be curious to know how the tech determined the Transmission was bad?

Tech determined transmission was bad when his manager said "We already sold this guy one transmission, let's sell him another! We need to make this months numbers so I get my bonus!"

Listen to everyone above, do all the recommendations before replacing the transmission...

Man, I hate car dealers and their service departments... Unfortunately 90%+ are thieves and prey on the unknowing because many mistakenly think that the dealership is the ultimate authority on their brand of vehicle...

[Vanguard]

Originally Posted by LuvMyV6

I took my 2017 V6 into the dealership for a transmission diagnostics. I had fingers crossed that I could get it serviced in time before it was completey done. Sure enough, the service department says I will need a whole new transmission. They're offering $7,700 for one of their brand new ones with a three year and 100,000 mile warranty. I can't afford that right now, and I'll have the car paid off in February.

My question is, how long has it been known for a transmission to last while shuddering? A few months? A year? Will it shudder forever? I'm working on getting a daily, which I was hoping to only do after paying off the car. This is also the 2nd transmission I've put into this car. Both around 60,000 miles and both outside of warranty.

Same tranny on my 2019 Corvette. There is a TSB for the shudder problem. As per GM, dealer is to flush and replace tranny fluid. If the problem persists they must change the torque converter. Just had my torque converter changed last week and the problem is solved. This work is covered by the warranty if you are still within those limits.