[Joshinator99]

Agree with Arpad. The A8 is a robust transmission that really comes alive with a tune. Get yourself a Circle D TC and a TCM tune and enjoy your car.

[Need4Camaro]

Originally Posted by arpad_m

Aw man, that sucks, you barely nudged past 60k, can't you sweet talk the dealer to still do it under some customer satisfaction program? Labor is probably going to cost you a lot even if the TC itself isn't earth shatteringly expensive.

As to the tune and upgrades, Ted Jannetty did mine and there is much more to the trans tune than disabling AFM. A good tune transforms the A8 into the great transmission it is, I have zero issues with it apart from the paddle shift delay (but that is a design limitation). I'm sure others can also do a great job, and hearing that you're considering flex fuel, cam and/or FI, I for one wouldn't mess with the TCM/ECM/FSCM tune but get that done by a pro shop.

J/W will there also still be a delay in the auto-stick (the actual shifter)? Thats usually what I use anyway.

If I for now go with a Circle D converter (stock lockup), and go E85, Full Exhaust and Intake, do you think Ted can tune for all of that at once?

[arpad_m]

Originally Posted by Need4Camaro

J/W will there also still be a delay in the auto-stick (the actual shifter)? Thats usually what I use anyway.

The lag is similar on mine whether I use the paddles or the shift knob, maybe a bit faster with the stick, but definitely not A10 and nowhere near dual clutch fast.

Originally Posted by Need4Camaro

If I for now go with a Circle D converter (stock lockup), and go E85, Full Exhaust and Intake, do you think Ted can tune for all of that at once?

Heh, that question is probably a mild insult in itself , I'm sure he can, just give him a call for a quote and ask any questions, they have always been helpful to me. Definitely shop around before jumping into these upgrades. Exciting times ahead for you

[Zr8000]

Originally Posted by Need4Camaro

Welp, I got good news and bad news..

Bad news first:
...My Powertrain Warranty expired... I for some reason thought it was until 75k miles, it was only until 60k and I'm at 61k miles. Car is still at the dealer regardless. I have an extended warranty that I paid for but I'll have to come out of pocket alittle for whatever repair is deemed necessary. I'm also 2 weeks out just for diagnosis. I have a loaner.


Now for the good news:
...My Powertrain Warranty expired...I can now do whatever the hell I want with my car.
I'm thinking of an E85 Tune as well as intake and full exhaust and maybe - just maybe a cam. Not sure on the cam. I may end up just going S/C
That all asside, I've heard of some members replacing the TC and doing a tune for a permanent fix to this issue. What exactly was done? Did they just tune out AFM or was something more tuned? I dont really want to stall my car. I put a stall in my 4th Gen and it doesn't really appease me for a street driven car.

Or should I just hold out for a ZL1?

I had one go out my 2018 truck. It was 5300 to have trans replaced by a dealer. Gm will warranty the replacement part for 100,000 miles but not the original one.i fought with them for 2 weeks over it trying to get them to at least pay for the part. I was able to get a 2000 dollar credit towards the purchase of a new vehicle in the next 12 months. They basically told me to f myself

[cmitchell17]

My shudder came back after I had a "triple flush" done, which isn't the newest TSB out and it used the older fluid not the newest blue label. I think it was 2 or so years ago when I had that done, but my shudder had been getting noticably worse, and I actually have the slip tables zeroed out in HP Tuners but that does not completely fix the issue, there are a lot of stuff we don't have access to in HP Tuners and just disabling the tables we have access to is not enough and it will still slip and shudder like in between gear shifts in transient states.

I called around to some dealers and after them saying they wouldn't even give me a price on performing the NA-355-TSB which I believe is the number for the latest one, I gave up and ordered the new fluid and a filter for about $100 and dropped the pan and drained the fluid myself.

Basically I bought 12 quarts of the new fluid (approximately 12 quarts is the full capacity of the trans and the cooler). I put my car on level jack stands, there is a "drain plug" thats not really a drain plug that you can unscrew and while the trans is cold it will let out a lot of the fluid but there will still be fluid underneath the drain in the pan. (if you unscrew this plug while the trans is at its fluid checking temperature (95-113F) then you shouldnt get much out of the drain plug since its designed to be at this fluid level when checking, so you fill it up until fluid starts coming out the drain then its at the optimal level.

Then I carefully dropped the pan trying to do one side first so it will drain out one side, ended up making a pretty huge mess but oh well. Took the pan off and cleaned it out and the magnets out and put the new filter in (probably didnt need a new filter but they are cheap).

Then I took a coat hanger and there is a little passage up around the transmission going up under the firewall and the coat hanger will pop up behind the motor when you have the hood open. I then took some 3/8 heater hose you can get from the parts store and drilled a hole through it and attached the coat hanger to the heater hose and pulled the coat hanger down back up under the car so it would route the heater hose down behind the firewall right to where the fill hole is on the transmission and a 3/8 inch hose is perfect outside diameter to fit in the fill hole.

I then think I put about 6 quarts in (estimating putting in the same amount that I drained) then took out the heater hose from the fill hole (but leaving the heater hose behind the firewall) and put the plug back in the fill hole and cranked it up and let the trans temp warm up to 95-113F (if you let it warm up too much you can underfill the transmission). Once it warms up to that range leave it running then take out the "drain plug" if fluid comes out you had too much in there and let it run out until it stops it is now at the optimal level, make sure the engine is running when you take it out.

I then drove it around for a day and it seemed like it fixed the shuddering. I still had 6 or so quarts left so I jacked it up again put 6 quarts back in it and put the fill plug back in. Now you are not supposed to do this because it would be overfilling the transmission and GM tells there service people this is very bad mainly because they don't want the transmission spitting out fluid when its too full because ATF is set on fire easy by hot exhaust. They also claim it can cause the pump to cavitate.

Anyway once you overfill it with all the new fluid you can put in it, I then cranked it back up and brake stalled it a little to get it to warm up and let it cool back down to the checking temperature (95-113F) then drained it again. This way I know I put as much of the new stuff in as I could. It would probably be better to try to drive it around and get the trans hotter, but I would be worried about it being overfilled and starting a fire. I am not sure if the 8L90s on the cars have thermostats that bypass the trans cooler when the fluid is cold but my guess is not since I rarely ever see my trans temp heat up past about 130 or so. If it does have a bypass it may be a good idea to only overfill it by a quart or so then go drive it around and let all the fluid mix around and drive it enough to where the cooler bypass opens and mixes the new fluid around in the cooler too. Then drain and repeat with another quart or so, this way you wouldnt have to drive it around and try to heat up the trans with it over filled by 6 quarts and cause a fire.

[cellsafemode]

nobody tried this stuff?
https://www.lubegard.com/wp-content/..._all_sizes.pdf

I have an 8L45 and i've been noticing some shuddering at low engine load when cruising in 8th gear. It almost feels like you're driving over line markers in the road that had been previously removed or sections of the road that have been rumblefied by big trucks braking hard on them. Bouts of shudder you can feel in the gas pedal that come and go at regular intervals when you can mantain engine load and speed.

[HCI2000SS]

Originally Posted by cellsafemode

nobody tried this stuff?
https://www.lubegard.com/wp-content/..._all_sizes.pdf

I have an 8L45 and i've been noticing some shuddering at low engine load when cruising in 8th gear. It almost feels like you're driving over line markers in the road that had been previously removed or sections of the road that have been rumblefied by big trucks braking hard on them. Bouts of shudder you can feel in the gas pedal that come and go at regular intervals when you can mantain engine load and speed.

I wonder if GM uses something similar when doing the latest fluid and flush procedure.

[cellsafemode]

I'm gonna amazon it up and see how it works.

[cmitchell17]

Originally Posted by cellsafemode

I'm gonna amazon it up and see how it works.

My guess is its not going to work because I think the problem fundamentally is that there is dissolved water in the transmission fluid which isn't going to go away even when the fluid heats up and no matter what you put in it, you just have to get rid of the fluid and put in the new Mobil 1 Synthetic LV "Blue Label" fluid.

[cellsafemode]

really, all you're doing in a non-100% fluid change is adding a hydrophobic albeit clean fluid to hydroscopic fluid which will allow the water to escape instead of being trapped. This additive thing is supposedly concentrated additives intended to be diluted into the existing fluid.. Effectively behaving like a larger fluid change than what it is.

Whether it works or not ..they seem to say it does.

I think if i have to do a fluid change fully....I'm kind of confused on how to do a full flush with at-home type equipment. Seems like the average plan is to do 6 quarts at a time, drive around drain that and do it again. Not very cost-effective ... probably 200 bucks in fluid alone for 24 quarts. Not counting the 100 bucks for the fluid transfer vacuum/pump

Though, I am really eyeing up a quickjack and this would be a great justification for it. But the more i think about it, the more i'm convinced I need that quickjack even if i dont do the full trans flush route.

[cellsafemode]

So I was warmed up, but not level, the front was on ramps and I'm assuming the apartment complex built the building on somewhat level ground...didn't bother taking a level down to check at the time since I'm not doing a full flush yet.

Over a quart of fluid drained out of the level check hole. I was surprised. I figured since it was tilted away from that check hole, i'd get little to no fluid. Car wasn't running though, so maybe that's why more fluid was down in the pan than expected.

in any case, once the quart an a half of fluid (more or less) drained out ...i shoved a quart of this additive (linked in previous post) back in and plugged it.

I drove it a few miles to mix it up and I'll do a test today on the highway to see if there is any change.

btw. my car has about 35k miles and the trans fluid was very blackish. Now I'm very inclined to change it all out

[cellsafemode]

after letting it sit for over a day after that quick run yesterday, i took the car out for a much longer drive.

The vibration i was feeling extremely regularly and reproducibly is gone. However I feel like i caught mine fairly early and I dont know how this would behave with someone who let theirs get bad enough that passengers could feel the vibration. My passenger couldn't before the additive.

I think if this was something added to the old fluid if you happen to have had it just added recently but prior to the new formulation ...you could get away with avoiding flushing all that still-ok fluid

My fluid is black though so I plan on getting rid of it all in the not too distant future.

[Need4Camaro]

^^ Noted, unfortunately for me, this is actually the second occurrance so I wouldnt be surprised if there is damage. The shop is recommending a new Torque Converter for my car. I'm believing my extended warranty will cover it, I just have to pay a $100 deductible. I'm hoping no haggles there. If they don't then GM may or may not cover it given the history of it happening before the permanent fix.

They are also stating they have to tune it. When the new converter is in, will this new tune of GM's prevent this from happening again or is there more I need to do to prevent this from being the future of this car?

[cellsafemode]

if the problem existing prior to warranty being lost and was worked on and the "repair" didn't actually fix it, then it should still be covered now that it's out of warranty since it's a prexisting issue identified while the warranty was still active.

Though, there's a lot of things that oem's should do when it comes to warranties that they dont in practice.

Not sure why a replacement torque convertor would require a tune, and i dont think the current tsb mentions anything about changing the tune of the trans to help fix the shutter issue. So that's odd to me. I thought the current fix was just new fluid and a full flush of the old tuff, with no need to even replace the trans filter.

in any case, if they replace the tcc and there is no evidence of additional damage caused by tcc metal fragments getting into your trans ...and they give you the new fluid.. i think that's their idea of a perm fix. The problem is the fluid (from what they've discovered). Not the mechanics of the trans itself.

That is, unless they're lying and the fluid is just a better bandaid.