I am at my 3yr required Transmission fluid change and my 7500 mile DCT filler change. ACDelco SKU: 19418016 Does not seem to be available. Due to the national backorder. Can someone confirm a alternative DCTF FFL-4 fluid that is accepted under the restraints of the GM warranty?
I have read in these within the forum, and I quote.....After contacting the Valvoline Techline, found that Valvoline 888705 is an alternative to GM DCT. Tech line contact 800 832 6825,
i have also read TREMEC and GM recommend specific products (Pentosin FFL-4,
Fuchs Titan FFL-4, and Delco DCTF FFL-4
depending on where you look) but do not
references a "specification". 2) FFL-4 is not a
specifcation there is no approving or licensing
authority - unlike API, or dexos, or GETRAG etc.,
3) the Valvoline Dual Clutch Transmission Fluid
lists recommended uses, but list no
specification approvals or licenses.
Seems like GM should be giving us some alternatives if they can not provide the required product in there current manuals.

Main information i would like to find out is can i use another approved fluid that will keep my warranty intact?

 

If warranty is a concern I’d leave the car parked till your dealer calls you when the DCT fluid comes in through the GM channels. I’m sure they will have it by Feb-Mar.
If you want to throw the dice on a 20k repair bill you can buy the Valvoline ( I personally would not) and at that point change it yourself.

 

Regarding "approvals" I think you have all the information in your summary. GM and/or TREMEC have, in different documents recommended the Pentosin, Fuchs Titan, and Delco DCTF FFL-4 products. Valvoline, on their website, if you use the product finder, will recommend the Valvoline product specifically for the C8 (using their product finder). AMSOIL will recommend a product as well. They are not GM approved. They may be fine, and some are reporting using the Valvoline product without issue.

 

I've been using Amsoil FFL-4 on both my C8 Z51 and C8 Z07, mostly using them at the track. I've not had any issues, and Amsoil does not recommend fluids on their site when compatibility is in question.. I went this route in hopes of marginally better high temp wear protection, not that these cars' cooling system would allow the fluid to overheat.

 

It's a shame that Porsche can put out a PDK DCT and recommend a fluid change every 12 years or 120,000 and GM can't do the same or even come close.

 

There are exactly zero Porsche owners that follow the factory change interval recommendation, and in any case, the PDK is a split sump DCT. The clutch fluid (FFL-4) is a separate sump from the gearbox that uses 75W-90 hypoid gear oil.

The C8 DCT is afaik the ONLY single sump DCT where FFL-4 fluid lubricates the entire transmission. Dana/Graziano, Borg-Warner, ZF/PDK, Getrag, etc.....ALL are split sump DCT designs and 90% of the performance car market.

There are a number of drawbacks to a single sump DCT, and as I've said before, the TR-9080 was a solution looking for a problem. Aside from shifting problems and solenoid issues (due to clutch debris), the TR-9080 tends to be noisy because thin FFL-4 DCT oil is lubricating numerous helical cut gear sets which shears down the viscosity. 75W-90 used in the gear sump of other DCT's is much thicker and tends to quiet gear lash.

My previous Stingray, and now ERay both get their initial DCT fluid/filter changed @ 2,500 miles, and then yearly after that with either Valvoline DCT or Motul DCTF Hi-Torque.

 

How does the Valvoline's viscosity compare to the Delco's FFL-4?

 

Very close to the same. Perhaps slightly thicker high-temp viscosity.

 

Yea 888705 is better than oem and that weird having to shake it is not required.

 

Anyone try redline DCTF?

 

Quality product.

Exceeds the AC Delco FFL-4.

 

I use Valvoline DCT fluid in my 2020 C8 Corvette with no issues. It is recommended by Valvoline.

 

Benefits of the Valvoline dct fluid is that its cheaper than motul, redline, oem and its red so will be a lot easier to tell if your engine or transmission is leaking. Joking, I hope your drivetrain doesn't leak fluids. Have been running Motul hi torque dct fluid for the last 10k miles with no complaints, will try valvoline on the next fluid change.

 

Do all these other than OEM brands mix OK together? I say that because when the pan is drained or dropped, it only takes 10 quarts to fill out of 12 quart capacity. You're mixing a coupe of quarts of old into the whatever new you're putting in. Apparently it does mix since no one is reports an issue, makes me a bit nervous though.

 

Are all of the fluid options dyed red? I don’t want a warranty issue with using the other fluid options.

 

So...while I stick with ACDelco DCTF-FFL-4, there has been no evidence of a denial of a warranty claim for using a different fluid. Of course, I don't think we have seen evidence of a warranty claim from anyone that is using a different fluid.

But if you you are using different fluid, you are likely doing it yourself, or possibly supplying it to a willing dealer. Either way, there will be a record of the fluid you used. If you are DIY, and you need to make a warranty claim, you will need to supply receipts for the fluid (at least both the Owner's Manual and the Warranty Manual -which say ok to do DIY but keep receipts). If you supply it to the dealer it will likely be indicated on your invoice. The certainly won't record it as 10 liters of AC Delco DCTF FFl-4. So, the color of the fluid will not be the only way to tell.

 

Do you need to purchase Techline connect $4000+ to flash TCM on GM cars with this Topdon j2534 tool?

 

This is my experience with the Valvoline DCT fluid in the C8.

My daughter has a 2020 Corvette Z51 and I have a 2023 Corvette Z51, and a friend has a 2023 Z51 also. They are all completely stock except for upgraded brake rotors. We track our cars many times per year on road courses with 20-30 minute sessions. When running similar lap times, the cars come off track with engine and transmission temps within 2-5 degrees of each other. Last year I took my 2023 Z51 to a Chevrolet dealership for a DCT service plus the two extra quarts. At the next track event, my transmission threw temp high warnings on the dash. I would drive around after the session to cool the car and the transmission temps would bounce around - I suspect because it was boiling into vapor. And the transmission was consistently running 15-30 degrees hotter than my friends. Also experienced many hard or janky shifts. Same lap times - literally racing each other on track the whole time.

When I got home, I looked at the paperwork and figured out they used Valvoline DCT part # 888705. I had no idea a Chevrolet dealership would ever use anything but OEM fluids. I finally convinced them the oil is the problem and they need to swap it out for AC Delco FFL-4 plus the 2 extra quarts again. They did this for free. I went back to the track and it was immediately better, but not fully back to normal. Then at the next warmer event it was back to the same problem - over temps, hard/bad shifts/etc. Now I am trying to get them to replace my transmission because it's steadily getting worse.

These cars do not overheat. Neither transmission nor Engine. We have run them at High Plains Raceway in 105 degree ambient temps(before the fluid fiasco). Nearly every other car there that weekend had heat issues. None of the C8s skipped a beat the entire weekend.

Note - the 2023 Track Prep document says this

"Any transmission level set or change should be performed at
your dealer. The transmission fluid used in the dual clutch
transmission is a specific transmission fluid. Use of unapproved
fluid may cause damage to the transmission. See your dealer for
the proper transmission fluid"

I would have specified AC Delco FFL-4 to be put in my car had I known I needed to. The Valvoline DCT fluid is definitely cheaper. I had never heard of it until this issue and I wish I still had never heard of it. I never experienced any issues with it during road driving, only at the track. And I never checked if it runs hotter on the street versus the other cars. Maybe it's ok for the street if some street-only people want to give it a shot? Never again under any circumstances for me.

Just wanted to give everyone a real world data point.

 

Sounds to me that they under filled the transmission….

 

Yeah, that's what I thought, too, considering there were also fluctuating readings.

I'm my experience, C8 Z51 did not overheat (no codes), but was definitely running too hot in stock form in hot days, at least in technical tracks of Pacific Northwest with limited straight sections. Adding the missing radiator on driver's side (V09 option) has substantially helped stabilize the temps below ~220 degrees F for coolant, which also helps with engine, diff, and transmission's longevity, since they're all cooled by the same cooling loop.