While I agree that using alternative fluids may be ok, I will offer my anecdotal story of using Redline MTL in my M5 and the shifting was just not as smooth as the BMW branded fluid. I also used a diff fluid in the LSD and then I got some noises at low speeds while turning. Switching to the BMW branded stuff fixed both issues. So, there are details in OEM fluids that may not be totally replicated in other manufacturers' stuff even if they have some form of specification listed on the bottle. But, I agree, the Valvoline stuff seems legit for the DCT. I may consider it next year when my fluid change is due.

 

Ruby Red on the Valvoline DCT and you don't have to shake it up before using like the funky AC Delco DCT fluid.

You can imagine on a fluid change a typical Chevy mechanic having, "No Clue" to shake every DCT bottle before pouring into the case. Like that's actually ever going to happen? It is the only DCT fluid on the market that needs to be shaken prior to pouring. Good reason to use the smoother shifting Valvoline DCT.

Valvoline DCT fluid has been in my C8 the last 10K miles. Maybe since mine is broken in, but it shifts better than ever before.

 

I don't mind to switch fluids when I do my change, it doesn't worry me, it would just be very convenient if the fluid I switch to is the same color as the Fuchs/ACdelco fluid in case it ever needs to be opened up by GM later on for warranty purposes.

 

Agree, no need to change to another DCT fluid until year 3 arrives and keep the factory supplied as is OEM fluid.

When my year 3 arrived at 22K miles that is when I moved over to Valvoline DCT fluid. At my 3 year fluid change requirement on my 2020 I had already previously changed my DCT filter 4 times with multiple HSF performed.

As previously stated, IF the Tremec 9080 goes out, IT goes out Early, before the first 5K miles. Sure you have 24 months before the drivetrain warranty is up and you can have the dealer change the fluid to the ridiculous $50 quart AC Delco which I feel does not perform and shift as smooth as the $8 quart Valvoline DCT fluid.

On my 3-year change I called three dealers and had them break out the cost for filter/HSF, fluid and labor. Chose the dealer with the lowest $Labor and provided them with the $8 quart Valvoline DCT fluid and $100 Rock Auto canister filter.

For good reason this C8 in 5 years has seen limited dealer time and will continue on that path without any type of various extended warranties. Sure this Tremec and LT2 engine now are properly broken in however, just pointing out since using the Valvoline my C8 DCT shifts smoother than the funky must be shake it up $50qt AC Delco product.

 

I'm surprised that after 5 years and 170,000+ cars produced, no filter companies have stepped up and offered an alternative to the insultingly overpriced $110 GM filter. I mean it's a pretty basic filter with no exotic/expensive materials used...perhaps someone who has contacts at one of these filter companies can drop a hint!

 

Oh the make 'em! Here is one (not recommending it):

 

There are non-OEM filters available. This might be the same as OEM but procured through a different supply chain, a knockoff, OEM reject, etc. I don't know if anyone has purchased one to compare it to the OEM filter.

 

Based on legit, this is as low that your going to find. Believe when the C8 first arrived in 2020 these filters were over $200.

 

At that price and 888705 valvoline fluid about $200 to diy a dct service, makes a yearly service doable.

 

888705 Valvoline DCT at $8qt no brainer and very popular with trackers. Been using now 10K miles, even though my Tremec was more than properly broken in, this fluid shifts smoother.

Also I'm following the Maserati MC20 TR-9080 gearbox fine filter change recommendation, "every 9300 miles or 1 year". Feel GM's filter changes are over extended for the Tremec DCT.

 

I’ve said several times that changing the DCT fluid/filter yearly with Valvoline shows the next buyer that someone cared about the car. THIS is the biggest indication of overall condition imho…..especially for C8Z’s and ZR1’s. I don't care what the C8 owners manual says, these cars are serviced yearly the same as Ferrari, McLaren, Lambo, etc.

I was on the fence about the McLaren 720S that I just bought, but when I saw the customized three ring binder the original owner kept with meticulous notes, receipts, and the cars yearly service history, I was sold.

 

You know, I wonder about this. I do my own routine maintenance and keep a meticulous log and record of everything done on my car. While it might give me an edge if I were selling my car compared to a similar car, I doubt anyone would be willing to pay anything extra for my car with 1500 mile oil/filter/DCT filter changes with routine oil analysis. I just don't think its important enough to most people.

On the other hand, if I were looking for a used car, I absolutely would not consider buying any car without having a maintenance history available and that I could evaluate.

 

For a typical 1LT/1LZ no option car with black interior, I would tend to agree. But years from now……a loaded 3LT/3LZ/3ZR with all the toys…..someone will be looking for THAT car. If they have a couple of options, and one car has nothing but carfax or dealer data showing the DCT has 20k miles on the DCT oil, while the other car has a similar three ring binder as the one I got with my 720S………shiiiiiiit (golly)……no doubt in my mind which car will get sold for a good price.

 

It depends on they buyer. Some would prefer a car that was been maintained per the schedule in the owner's manual using the fluids recommended in the owner's manual over a car that has been maintained more frequently with fluids not recommended in the owner's manual.

 

Hmmm.....how did "maintenance per the schedule in the owners manual and using the fluids recommended in the owners manual" work out for 600,000 L87 equipped GM vehicles?

GM's recommendation to run the DCT oil for 22,500 miles in the only single sump DCT used in a performance car, with regular use of launch mode and high rpm driving is highly ill advised.

 

Would appreciate input...I have a new 2025 that I plan to do my own maintenance. I have seen multiple videos on changing the DCT filter early as part of the flush procedure. However these videos do not show a transmission fluid dump and refill, just the filter. Is there any negative to replacing the fluid early? Is there any specific procedure for draining and replacing the fluid? Thanks in advance.

 

I changed my filter and fluid at 2450 miles. I track my car so my maintenance schedule is at least yearly for both. No issue with an early change. If anything, it'll get some of the break-in material out that's not captured by the filter. Have the car level, remove the fill plug first to make sure you can refill before draining. Fill until the fluid just starts flowing out of the fill hole. Install plug and run the car in D and R for 30 to 45 seconds each 4 or 5 times. Remove till plug and top off until fluid just starts to flow out. Button things up. The GM procedure has fluid temp ranges for fill and check I believe. I don't worry about that personally. I do a 2 liter track fill on my '23. I'll get about 11 liters out on a drain so there's always fluid remaining within the case and passages.

 

I have posted in the past. I currently have just over 10K miles on my 2023 Z06. I first changed all fluids/filters at 550 miles and every 1500 miles or so thereafter. Also changed the trans fluid twice, sent out a sample for analysis, cut all my DCT filters open and performed the hydraulic system flush twice using the GM MDI2 diagnostic interface.

When I did the flush, I first removed the in service filter and replaced with a new one. After the flush, I removed this new filter and replaced it with another new filter. I cut both filters open for inspection. Both times the filters I used for the flush *only* looked new. Based on my observations, I would advise that if you change the DCT filter regularly and often, you will not need to do the flush procedure. Also, in my view - especially when your car is new, the condition of the used filter should dictate when your next filter change should be done. For example: the first few filters had a lot of trapped debris. Each subsequent filter change showed decreasing debris and I might now start extending the mileage between filter changes. If you have significant mileage greater than, say, 3750 or half the 7500 miles GM recommends changing the filter, I would do the flush only after removing the in service filter on the unit. And again, If you keep a clean filter on the trans, I wouldn’t even bother doing the flush.

 

The only negative, I think, is to your wallet. Just remember that if you change the filter before 7000 miles, you need to change it again between 7000 and 8000 miles.

 

That problem has nothing to do with following, or not, the maintenance procedures. Those owners could have change the oil every 1000 miles and it wouldn't have corrected the manufacturing error that caused the issues.