I changed my DCT fluid and filter in my 2020 C8 with 888705 May 1st. I was told I was throwing a hand grenade in there.
2000 miles later, everything is just fine. Lots of spirited driving and launches, not one issue.
What made me? The track rats are doing it and it's a lot cheaper. And it meets FFL4. Cost me about $100.

 

Pardon The Interruption ....
Question about transmission service. I'm fully aware of changing the DCT and fluid at specific intervals. However is the second (internal) trans filter needed to be changed at any time. Thought the internal was only needed to be replaced if an internal repair was done. Plans are to do DCT filter and fluid change @ 22,500mi. My 3 years will be around the same time for this service.

 

The internal filter is not ment to replaced unless you drop the pan for some reason, like for a repair.

 

 

I bought the 2022 vette in March. The dealer threw in the first tranny service, but neither of knew all the fluid needed to be changed at three years. The three years will be up in October.

We both didn’t know at the time about the second service. He claimed he wouldn’t pay for the extra service. I offered to pay for the fluid and he pays the labor. He said no, but the service writer spoke up and calculated what Chevy will pay for the filter change and took that away from the big service. So the total cost for me was $530 instead of $1000. Ok I can buy the “GM” fluid for $330 so I’m paying him an extra $200 to change it.

I see a lift in my future.

I can live with that. Also took a fluid sample for testing. I’ll share it when it comes back.

Joe

 

I bought a lift (VEVOR) but after getting it decided two jacks and jack stands would be a lot easier to deal with and sold the lift. I’m old and my wife and I did the drain and fill. Took our time but it was very easy. Also added the extra 2liters.

 

I think everybody clearly understands what he meant

Valvoline DCT service on a C8 costs me $175 and takes 2 hours including HSF procedure. Local dealer charges $1,300 = $1,125 savings = paying myself $560/hr.

I recently heard my neighbor down the road is worth $150m. He has a big solar array in a field adjacent to his $10m house with panels that track the sun. Birds constantly nest in them and jam the tracking. I saw him out there on a ladder in the scorching heat last week sweating bullets futzing around with them. I stopped and rolled down my window.....yelled "Its too hot to be out there today"......he yelled back "they charge me $300/hr to do this, for that much I'll sweat."

I don't live in a $10m house and I'll wager you don't either. My neighbor does and he's worth $150m because he doesn't pay $675 for 10 minutes of unskilled work.

 

Why did you do the HSF with the drain and fill? Did you do the filter too?

 

GSvette can answer for himself, but if dumping the fluid, why wouldn’t you first do an HSF which uses the fluid to flush debris out of the valve body and hydraulic circuitry before putting new fluid in?

 

My understanding is the HSF is part of the DCT filter replacement to flush debris into the DCT filter before doing the DCT filter replacement. It is not part of the drain and fill.

 

This should explain everything DCT related, including HSF...
https://www.youtube.com/live/eDGJ-Zu...v5qh8eB6UrOHGI

 

LOL!

If there is one place on the web that you should NOT be looking for accurate, helpful guidance for your car, it's this channel. I simply looked at snippets of this video and sure as ****, there is bad and misleading info. Justin does not know much about cars in general and knows less about the C8.

It is too bad that GM puts a chastity belt on their employees because inside information from qualified people is what is sorely lacking in the Corvette community. Even with this, people attached to Corvette who make public appearances sometimes make statements that are vague, open to interpretation and lead to more questions rather than clearing some issues up. And with regards to this, just remember that the sole purpose behind GM's existence is to make money. Often, they don't want you to know the truth about things and, in fact, encourage people like those in this you tube channel to broadcast most of the official GM line of BS. If you have been paying attention, however, there are a few very qualified and knowledgeable people here in this very discussion who do things different from what GM tells you to do. That should raise questions in your mind about the validity of the you tubers when you hear them telling you a bunch of BS. And, don't forget, these people are on you tube to make money. They don't do much of anything else.

There's much more about this channel and Justin that I know about, but I'll just leave it here. I would encourage anyone to view this channel with a critical eye and try to find corroborating evidence before coming to any hard conclusions.

 

So, without clicking on whatever that is, is my post correct or not?

 

Because the car does it while you drive.

 

Not 100%. What the car does and the computer controlled HSF procedure are not exactly the same.

 

According to some, you're actually doing the same hsf process as you drive. Don't blame the messenger. Rick Conti and horsepower obsessed (youtube) have the same mindset. Glad we can agree to disagree respectfully.

 

Understood. I’m sure others will be here soon with the video interview with the Corvette engineers stating they are different but it is okay for the do it yourselfer to not do the HSF while doing the DCT filter change. Had nothing to do with the drain and fill.

To repeat the computer controlled HSF and the “routine” the car does driving are not the same.

So my post, correct or not?

My understanding is the HSF is part of the DCT filter replacement to flush debris into the DCT filter before doing the DCT filter replacement. It is not part of the drain and fill.

And the discussion was that a person did the HSF while doing a drain and fill and I asked why since the HSF is part of the DCT filter change not the drain and fill. The person said HSF not the “routine” while driving.

 

The (I think incorrect) idea that the highway routine is the same as the HSF originated from a statement by Josh Holder. Its below. Josh said there is a highway routine that forces more fuid through the filter, but he did not say that highway routine is the same as the Hydraulic System Flush.

I have also attached a clip showing the description of the HSF found in the service manaul. Its a bit more involved than just "forcing more fluid through the filter".

And another thing. As most know the routine for the HSF does not even reside in the earlier model year cars - but does reside in the later model years. In the earlier years, the scan tool must first load the software before it can execute the HSF. This is why, at least for a while, some aftermarket scan tools could not do the HSF on the earlier model years ( I think some do now though). With later models the HSF software resides in the car - and can be initiated by most aftermarket scan tools. But the point is, your not going to be executing the HSF while driving down the road.

"Josh Hoder: "The hydraulic system flush does kind’a the way its described. It forces transmission fluid through the fine filter that you replace. So, at a dealership they can hook up the dealer service tool to the and run a routine that will tell the trans control module to do this fluid filter flush. And because the car is already hoisted on the rack, the technician’s already got the panels off, there’s some other work he’s doing, this kinda happens in parallel in the background. So we’re doing it at a dealer visit because we can. And we can take the last bit whatever contamination might be in the oil and get it into the filter before the technician replaces it. Do it yourselfers have become nervous that hey now I can’t do it myself, I don’t have a service tool, I can’t force this routine. You don’t have to do the routine. Like I said we do it because we can, but the fine filtering routine happens during normal driving anyway. In fact, when you’re driving steady state like say down the highway, we run a routine in the transmission that will force more of that fluid through the fine filter. So normal driving is doing this. If you are a do-it-yourselfer, you don’t want anyone else touching your car, you can change the trans filter without running this routine."

 

What your transmission does while driving IS NOT THE SAME as the HSF. Stop the BS right here. I posted in the past how to accomplish running maximum flow through the filter and this came to me straight from Tremec engineering in a three way conversation. Maybe no one was paying attention. Under certain driving conditions, the pump output will go to max and push max flow fluid through the filter. You can replicate this with the car stationary as well. However, fluid will not cycle through the valve body solenoids and oil channels. Holder's statements were very misleading. There is a lot of BS circulating in the Corvette community. Stop spreading falsehoods.

 

Guys

Has anyone sent out their tranny fluid for analysis they can share? I just had the service performed at the dealer and they did the flush and filter change. I’m sending it out just to see what is in it.
With all this fluid questions surely someone has been doing this? Right? I’ll share mine when it’s completed if you’d like.

For the background my 2022 had 7600 miles on it and it will be three years old in October. This should be the most soil you will see in 7500 miles. (Unless you run it hard like track after the first 7500 miles). I say that because of all the break in going on with a new tranny. (Only a gut feeling I’ll see at the next test). I cannot see any sentiment in the fluid so I’d like to know if we are talking 6000ppm or 60ppm of material.

With all this tranny fluid and “candy trannies”(wait can I still call transmissions trannies)? someone has to have a few analysis done.

Joe