Ok....still I'm unclear on their procedures and dates....I thought that the triple flush was the first attempt (with same fluid)....then TC replacement, if needed....

After it was determined that the fluid was the problem, only a single flush with the upgraded fluid was the procedure....

I'm wondering if flushes and TC replacements were done before the upgraded fluid was put into use....If all the triple flushes, TC replacements, then "single flushes" were done with the new and improved trans fluid, then I stand corrected. Thanks.

Yeah, a re-read showed you are correct...I misunderstood the triple/single flush business...

"So, what is the service procedure? Once we determined the issue was due to the quality of the friction modifier in the fluid, we developed a service procedure to flush and fill the transmission fluid 3 times, which eliminates most of the shudder concerns. This service process may not work for a vehicle with shudder that goes too long without service, in which case it will most likely require a new torque converter. Since we started using Dexron HP transmission fluid in March of 2017 both in production and for service, we believe we have basically eliminated the shudder. When used for service, it only requires a single flush and fill.

You are missing or ignoring that Al said he changed the Camaro’s production March 2017 and was clear he was only speaking for Camaro. Meaning other models or divisions did theirs later.

I'm not completely confident in the answer but I'll take it. Worst case scenario I already accepted I should just go and get the slip values tuned out instead.

The answer sounds plausible to me and I could see how a fluid spec that wasn't quite good enough could lead to the hit and miss issues. Also, I've been around a few automatic transmissions in my life (not an a8) and none of them used the torque converter in any way to regulate line pressure so I'm not seeing the slippage causing low line pressure. Maybe too much time has passed me by since tech school.

Not an expert either, just parroting what I've read here... Apparently, the line pressure to the torque converter is reduced under certain loads / gears. It sounds like this is done to cut down on pumping losses, which in turn increases fuel economy. Less line pressure = more slip at the converter. Add poor: fluid quality, converter material or converter machining and there seems to be a recipe for burning up the TC.

GM should be proactive as someone above said. If there's A date, every car built prior, should get the triple flush and TC replaced

I personally appreciate the backing here... although, since I fall into that category, I'm not certain how I feel about the car being torn apart without a really solid reason (concerned about collateral damage). A free single flush and filter change, sure thing... seems to makes sense. A triple flush may be overkill. No one really knows, and for me that's the issue. :noidea:

Thanks for the clarification, Al. I had the flush done at 15,000 and then the TC replacement. However the shudder returned at 18,000 and has been increasingly evident. I will make an appt with dealer next week (I did not want to chance driving it during snow season).

What I don't understand is, if it got a new TC and the proper fluid, why would it be happening again? At this point it only seems to occur when in V4 mode (which, I guess would be light throttle).

thanks,


-bill

Do you happen to have any paperwork that shows they used the latest recommended fluid?

DEXRON® Brand Product Descriptions

DEXRON® Automatic Transmission Fluid (ATF)

Modern ATF typically contains a wide variety of chemical compounds intended to provide the required properties of a particular ATF specification. DEXRON® ATF contains the prescribed combination of additives that improve lubricating qualities for your GM Vehicle. These additives include anti-wear, rust and corrosion inhibitors, detergents, dispersants and surfactants (which protect and clean metal surfaces); viscosity modifiers, seal swell additives and agents (which extend the temperature range of the additives' application); and anti-foam additives and anti-oxidation compounds to inhibit oxidation and improve fluid stability. DEXRON® offers two varieties of ATF, Standard DEXRON®-VI and DEXRON®-HP (High Performance), used in situations where low temperature fluidity and potential fuel economy are priorities.

************************************************** *********

I found the above at GMdexron.com....http://www.gmdexron.com/overview.aspx But I could not find anything on it being for sale or available anywhere....I googled dexron hp atf, but only got info for dexron-VI for sale, but nothing for Dexron HP....just trying to find info on Dexron HP atf.....Hopefully it does exist, and dealers have been using it....just can't find it for sale anywhere....????...Maybe I'm searching wrong or something...???

My 2016 manual says to use GM part number 19300536.
But I read on a corvette forum that that part number has been replaced with 19353429.

It’s Mobil 1 the dealers have it.

Makes a lot of sense to me. Sounds a lot like the difference between putting and not putting friction modifier in when you change the fluid in a positraction axle. Or not putting in enough of it.


Norm

Yeah. It looks like it's pretend and extend. We do have 5 yrs 60,000 miles to get this fixed repeatedly, correct?

It makes business sense to do it this way. Such is life.