Hello all, I am having the dreaded torque converter shudder on my 2015 Corvette I rebuilt from Salvage. I figure we may be in a situation where most of these cars need the torque converter changed ever 30k miles so I was planning to just learn to do it myself.

After confirming the issue, the dealer did offer to do the triple flush for $1500 (I have no warranty). I don't have the pumps to flush it myself, and just the fluid is probably $600 of that price. Does the triple flush actually work? Or is this just a desperate step I should skip? I am looking for first hand accounts, but any input appreciated.

Update: Ok, I feel like the triple flush worked... sort of. I still feel a vibration, it's faint, but I think it's still there. Previously it was faint at times and very noticeable at others. The RPM variation is gone, even in V4 mode.

I think I will consider it "fixed" until something bad happens and I will start using the range AFM

 

Do they guarantee the triple flush working, at least for a set period of time/mileage? If not I'd skip it. To me it seems like a temp fix at best. Actually I'd probably try the Range disabler first and see how that goes. You'd want one of those anyway, even if you get the car fixed.

 

I agree with Daffy that the $1500 triple flush isn't going to be a permanent fix and it may not do much at all if your torque converter clutch is severely compromised. I believe the new fluid probably contains a friction modifier to help a distressed clutch work better but by the time it is shuddering damage has already occurred.

As Daffy advised I would add the Range module now (or drive in manual mode) and plan on saving the $1500 to replace the torque converter at some point, especially if GM comes out with one that will actually stand up to the V4 mode wear.

With the number of failures it is very likely GM will be having to extend the warranty on these torque converters and they may well face legal action given the problems extending across the line (it isn't just Corvettes having the issue and it shows up in some very high volume applications). If either of those events occur even though you have a salvage/no warranty you may fall into a gray area and receive some assistance if the corporation is forced to admit that the part/control system is a flawed design. So I would try to take a less expensive approach and see what happens over the next year.

The one wild card for me in this is how much of the clutch material is circulating in the fluid doing other damage and that would be a reason for getting the offending material out via a flush and fill. Only GM has the exact data to know all that is going on with this A8 situation and they aren't publicly sharing that info.

 

After a triple flush how does the driveline know it has new oil ?........unless of course the old fluid is contaminated with TC clutch material , a wear characteristic of designed TCC lock up/release at a rapid rate ? .................just asking the question ?

 

I expect the improvement from the new fluid is due to a friction modifier present in the new fluid. All automatic transmission fluids contain friction modifying agents (just as do the fluids for limited slip rear ends) but I expect the new stuff is specifically targeting the issues resulting from clutch wear.

 

I can only hope you are correct...........

 

Luke42 can you briefly describe what happens during this shuddering. I also have a 15 A8 with 38,000 miles. I get no fluctuation of rpm's or hear any strange noises but I do feel something during the V8 to V4 change. I want to blame old or badly paved roads for the feeling.
Thanks. Jim

 

I have the same feelings and had a new TC installed last December. I only have 2k miles on the new TC. I've decided to use a Range in an effort to buy time. I also bought a GMEPP to extend my warranty coverage.

 

I did the triple flush on my wife's 16' Camaro SS A8 that developed the shudder at 10k miles.... The triple flush completely solved the shudder problem. Now at 17k miles, its still smooth as glass. Not sure if its a temporary fix or not but....it definitely solved the problem.

My dad has a 15' Z51 A8, 5k miles it developed the shudder. He did the triple flush and 1500 miles later, it is still good, smooth as glass.

I'm not sure if its the actual flush process, or the changing in fluid types that solves the problem but...it does help.

Not sure I'd pay $1500 for it though, I'd definitely shop around....

 

Had the triple-flush done on my '17 GS done 4 months ago and it worked. I have since been using the Range module 100% of the time until others can update on longevity of this fix.

 

Why should anyone have to pay $1500 to have this done, I thought it was covered under warranty??

 

^^^^ He noted that his car is not under warranty...

My question is should they/will they give us the triple flush even though we are not currently experiencing issues? Seems like it might be a good preventative measure.

 

Can't speak on a c7 but it worked beautifully on my 2015 Sierra 1500 SLT. It has the 8 spd transmission with the 6.2l engine. I had my doubts when they suggested this step but it has not had an issue since when I pulled my Corvette to Bowling Green, KY for the April Bash. It was acting badly on my trip out and back. Since the Triple Flush I have had zero issues. I have probably driven it 3,000 miles since the procedure. I have also read countless posts on the GMC and C7 site that it has worked to their surprise as well.

 

Shudder started at 7500 miles, only when I had it in auto mode, and AFM activated around 1500 rpms. When I put it into manual mode the shudder went away.
Had the flush done at 7800.
I'm at 9000 right now and all is fine in auto, but I have started using the manual mode much more often.
For what it's worth.
Good luck!

Update:
I got about 2000 miles out of the flush. TC replaced at 11,000 miles. So far, so good with 14300 on the odometer, but I am using manual mode far more than I want to, in an attempt to avoid any more issues.

 

^^^Glad to hear that several folks are experiencing positive results with the triple flush. Very encouraging...sounded like a far fetched resolution when I first heard about the TSB, but perhaps there is more to it...

 

You will feel a rumble like the mildest rumble strip ever intermittently even on a flat newly paved road. My RPMS fluctuate by about 100 when cruising above 60 in V4 mode, 10 rpm fluctuation is normal. My vibration DOES NOT go away in manual mode.

$1500 is legit for this. I had to put 6 qts of this fluid in when I rebuilt it (transmission cooler had been ripped off) and it cost me $250 worth of fluid. I think a full flush takes 12 quarts or something like that. I do believe you have to remove suspension parts to get to the transmission filter as well.

Thanks guys, I think I will try the flush and see if they will give me sone kind of warranty against torque converter replacement should it come to that.

 

How much is a new TC and new fluid? You already did tons of stuff to bring the car back to life. I'd guess you could probably pull this off too.

 

New TC without flush is $2100. Dealership's Corvette tech says he has never had the flush not fix the problem in all sorts of vehicles.

peehaps the triple flush is so effective that GM issued that new bulletin.

no warranty by dealer that this will work or that a TC replacement will not be required.

 

A new TC is $900.00 and labor to change it is 2K, not sure if fluid and filter is included.

 

[QUOTE=Luke42_02;1595222241]You will feel a rumble like the mildest rumble strip ever intermittently even on a flat newly paved road. My RPMS fluctuate by about 100 when cruising above 60 in V4 mode, 10 rpm fluctuation is normal. My vibration DOES NOT go away in manual mode.


Same here.