Foxwell NT 510 elite for GM works both flush and leak test on 23-24. Pretty simple process once you get the scanner. And if you do, the test takes approximately eight minutes and you do have to depress the brake pedal for eight minutes, if you let go the program quits and you start over.

 

this was the best investment I’ve made so far. I use to have a midrise lift which was nice, but nothing beats a 4 post.

 

I believe the tool is the NT510 Elite for GM. There s also a video on YouTube. C8 DCT Filter Change with Flush that is a step by step procedure using this tool.

 

I went to the Chevy dealer today to make an appointment for a few weeks from now. I wanted the oil & filter changed, the DCT fluid replaced and the additional 2 liter track fill for the DCT. I confirmed 2 things seen in this thread.

1) The dealer service advisor made the appointment for me but warned me they might not have the DCT fluid, as they've been running short. I asked if I could bring my own and he said yes.

2) I looked on RockAuto and found the 104130 fluid for 25.79 / quart (their term) I ordered 12 bottles to be delivered this coming Friday.

 

As per several earlier threads I started, there is nothing special about GM FFL4 DCT fluid.......except the ridiculous high price. Just use the plentiful supply of Valvoline 888705 FFL4/DCT fluid and be done with it.......$6.75/qt @ Rock Auto.
https://www.rockauto.com/en/moreinfo...choice=0-0-0-1

My previous C8-Z51 loved the Valvoline DCT fluid for several thousand miles, the guy I sold that car to has been just fine, all the track guys around here have used it for years, and my 2025 Eray will use it A-ok as well. My McLaren tech also recommends Valvoline DCT for my 650S as well as for Lambo and Ferrari.

I own this scan tool:
The Creader Elite GM tool does all of the DCT service procedures.....shift check, flush, leak check, etc.

 

You must own a 2023 or newer C8 then for this to work. Just clarifying because others will come across this and try it on a 2020 - 2022 and it won't work.

 

Excellent information. Thank you

 

why won't this work on a 2020 - 2022? Is there another way to do it on the earlier models?

 

Same in SW FL. I received service bulletin dated October but received in November from Chevrolet for my ‘21. I’ve made appointments with 2 dealerships and have been informed at arrival that fluid is back ordered. Transmission filter was replaced but I wonder if fluid level was topped off. O’Riley’s wants to sell me Pentosin. Probably would void warranty if it’s not already.

 

The way I understand it, the 23 and later models have the flush routine built into their software and the scan tools just enable it to run. The earlier models don't have the routine built in and require a GM computerized tool to run the flush routine.

 

I believe the software is different.

 

Ran the hydraulic flush today on my MY24 with the CReader Elite. Easy to do once you find the routine location. Garage was 44 so it took 40 minutes of idling to heat the tranny temp sensor up to 61C before the test would run. Ran the test outside in neutral and braked for 8 minutes and put directly back in to garage.....20F outside). Test was just over 8 minutes like everyone states. You don't feel or hear anything other than the 2000rpm engine which is not that loud even if you do it late at night.

 

The software / hardware is different. I don't think anyone knows what the difference is 100%, but we know there are differences between the 2020 - 2022 and 2023+ model years.

If you have a 2020 - 2022 you'll need an MDI2 device (or clone) and work through the GDS2 computer system as shown in this thread:
https://www.corvetteforum.com/forums...d-gm-gds2.html

Note, the BOSCH MDI2 unit is ~$750 - $1,100 depending on where you get it. There are clones of this hardware available, and they work, but due to the nature of uh... their legality... it's not discussed here on the boards from what I can tell. You'd need a device capable of CAN FD protocol, and don't fall for the blue MDI2 units. If you want a clone that looks like the BOSCH unit you'll need a red unit. Otherwise there are other CAN FD clone hardware available.

2023+ models can buy a handheld off of Amazon and do what is needed though for under $200.

 

The C8 Corvette uses GM Global-B vehicle architecture. All of it is AES-256 encrypted and uses various security and key-exchange methods to ensure onboard systems are secure.

There are three key aspects of C8 Corvettes and other GM Global-B vehicles (except C8 Z06):

1. Security. Uploading and downloading privileged code and service software from dealership tools and systems for routine service items is unnecessary risk and exposure to exploits.
2. Right to repair legislation. Requiring restrictive, proprietary, and expensive hardware/software tools for routine software is asking for a class-action lawsuit. See John Deere for how that is working out.
3. Supply chain issues. MY2020-2022 C8 Corvettes used an early version E99 ECM that had limited nvram/flash storage capacity. The smaller capacity chips were discontinued by the supplier, and GM was forced to upgrade capacity.

As a result, in MY2023-later Global-B vehicles, GM decided to include onboard most of the service routines that previously required MDI2 hardware/software tools. Since the software service routines are read only, and securely encrypted onboard the E99 ECM, overall security is improved by reducing the amount of proprietary GM IP that is in the open, sent over the internet, and stored on computers and tablets at literally thousands of dealers globally. All that is required is a scan tool that can issue a read-only API call over the canbus.

This efficiently solves the above issues and Kudo's to GM for making the changes. The Z06/ZR1 use a completely different and bespoke Bosch ECM/TCM and none of the above applies = GM dealership only service for those cars.

On my new 2025 ERay, the Launch Creader picked up dozens of new service routines specific to ERay. I am amazed that GM allows this level of service access on a vehicle they say is the most complex they have ever built......on a $150 tool.

 

Appreciate you breaking this down for everyone.

I edited the quote for space, but the Right to Repair legislation is why I think gm should have offered the ability to upgrade the ECU for 2020 - 2022 models. I'd be much happier with a new ECU and a $150 handheld vs. what I've had to do to enable running the procedures needed to properly take care of my purchased vehicle. I had my dealership change the DCT fluid and filter when I purchased (a used 2021 in 2024, it was due for the 3 year change at less than 15,000 miles). The original filter had been changed in the correct interval, but I asked as part of the negotiation to have this service included. They did it, but this winter as I've taken the car apart to do this again (because I've tracked the car enough in this year), I see they severely damaged the top brass fill plug the service manual says to use for the track overfill. I can't trust them to do the job correctly, so I'm going to continue to do it on my own... but gm has made it difficult and expensive simply because of my model year of purchase. Had I been an informed buyer about this, I would have waited and purchased a Z51 which didn't require the track fill and was easier to work on with inexpensive handheld devices.

 

Have you tried Rock Auto? I was able to buy 12 quarts at a much cheaper price than dealers.

 

Thanks is this LEGIT to use? Also, can this be mixed with the AC DELCO to at least "top off" when changing filter?

 

You'll have people saying they use Valvoline (not sure if it's the fluid you posted) but in my opinion the manual says to contact your local service center and every one of them says use the AC Delco.

 

Just a FYI I bought a Foxwell NT710 and it works perfectly on my 2022 Z51 HTC. What some people were doing wrong is not waiting for the car to warm up to 170 deg before running the flush test and trying to run the leak test after the car was warmed up, it needs to be cool as in right after the oil change.

 

I'm sure some may be doing it wrong. But, in the past, aftermarket tools would not initiate the HSF on earlier models but would on later models. That is changing now. The info about the HSF software not residing on the earlier models, that was posted on this forum, came from a maker of one of the aftermarket scan tools (in the past). And it was explaining why their tool would not work on earlier models. The reason they gave is that the Hydraulic System Flush software did not reside in the TCM in earlier models, and so the tool must first install some software before executing it. And at that time, the makers of that tool had not worked out the details of how to do that. The later models include the software in the TCM, so it was only necessary for the scan tool to initiate the HSF routine already in the TCM.

Are you saying that was never true? It was always just user error?

The Hydraulic System Flush was not even a procedure in the earlier Service Manuals. It first appeared in a bulletin with a procedure to address certain DTC, that included the HSF. Later revised versions of the bulletin were updated to delete the procedure from the bulletin, instead referring the tech to the procedures now in an updated Service Manual.