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For any of those that have done a full trans fluid change, is there any special procedures after the initial fill and level checks? Running through gears, fluid temp, etc. Also, has anyone replaced the internal filter that's located within the trans (with pan removal)?
For any of those that have done a full trans fluid change, is there any special procedures after the initial fill and level checks? Running through gears, fluid temp, etc. Also, has anyone replaced the internal filter that's located within the trans (with pan removal)?
I am interest in this as well - especially as it applies to the "routine" transmission fluid change to be performed at three years or 45000 miles. Do they change the internal filter? I know they will change it in response to certain issues, as I just read another thread where someone reported that. But do they change it for routine maintenance (as the Service Manual appears to say)?
I'm planning on doing all my own maintenance including the full trans fluid change. I'll be changing the internal pan filter as it makes no sense not to. Just curious about the initial routine to get the new fluid were it's supposed to be before topping off.
I am interest in this as well - especially as it applies to the "routine" transmission fluid change to be performed at three years or 45000 miles. Do they change the internal filter? I know they will change it in response to certain issues, as I just read another thread where someone reported that. But do they change it for routine maintenance (as the Service Manual appears to say)?
The internal filter does not have a maintenance schedule and is considered to be "lifetime" for whatever that's worth.
Why do you think a trans flush is needed? Is your C8 high mileage?
No... just planning. The first full fluid change is at 45K or 3 years whichever comes first. Although extremely short in duration, that's what you need to do to ensure warranty compliance. Can't take much effort to drop the pan and replace the filter and gaskets.
What does it take to change fluid? Do you drop the pan like an automatic trans.
I was thinking of changing oil and filter sometime way before the recommended 45K change.
Since contamination has been a problem, then changing fluid makes sense to me.
There's a drain plug in the trans/pan. Looks to be a two piece pan gasket and a filter in a plastic housing. Seems straight forward. Just curious about the fill and check procedure. Many modern trans have fill and fluid temp procedures now.
The internal filter does not have a maintenance schedule and is considered to be "lifetime" for whatever that's worth.
That's right - the Owner's Manual does not explicitly say anything about that internal filter. But it does call for a transmission fluid filter change at 3 years or 45000 miles or when the life monitor says so. The procedure I found in the Service Manual appears to include removing and cleaning the pan (there are two magnets in it), and removing and replacing the internal filter. The procedure is also actually listed as a Maintenance Item in the Service Manual. And that is the reason I am wondering what the service department actually does.
As for the internal filter being "lifetime" - as far as I know, that was a statement made in an automotive review article of some kind. I can't find that right now - but I think RKCRLR found it and posted a link to it. But I don't find it in the 2020 Service Manual, and in fact it has a procedure for changing it. I'm not really insisting that it is supposed to be changed - I am asking what is actually done when folks take the car in for a routine Transmission Fluid change. Edit: See post 10 - the "fill procedure" actually includes both drain and fill, and does not call for removal of the pan, nor replacement of the filter.
Last edited by Andybump; Dec 30, 2022 at 08:01 AM.
There's a drain plug in the trans/pan. Looks to be a two piece pan gasket and a filter in a plastic housing. Seems straight forward. Just curious about the fill and check procedure. Many modern trans have fill and fluid temp procedures now.
Here is the normal fill procedure, from the 2020 Service Manual. That part about shaking the fluid to stir up the additives is interesting. It does call for running the engine and rechecking the level. Edit: I should also add, although this procedure is call "fill procedure", it actually includes both draining and filling - and that suggests that it is done without removing the pan and replacing the internal filter.
Last edited by Andybump; Dec 30, 2022 at 07:58 AM.
Regardless of that the service guys are trained to do I'll be changing the filter. There's no such thing as a lifetime fluid and a lifetime filter. Especially with this DCT that generates clutch debris over time (and especially in the beginning of life). Now I do think the 3 year change even if the mileage is not at the 45K is nonsensical. But that's what you need to do to stay out of the warranty argument. I'll be doing all my routine maintenance work including trans filter/fluid changes. The coolant change could pose a challenge to based on the volume and length of tubing runs and potential trapped air.
Here is the normal fill procedure, from the 2020 Service Manual. That part about shaking the fluid to stir up the additives is interesting. It does call for running the engine and rechecking the level. Edit: I should also add, although this procedure is call "fill procedure", it actually includes both draining and filling - and that suggests that it is done without removing the pan and replacing the internal filter.
......... Now I do think the 3 year change even if the mileage is not at the 45K is nonsensical. .......
A thought on that. Its been stated that other cars that use the same fluid do not have the time out requirement. But I found it interesting that the fill procedure says to shake the fluid to mix in the additives before filling. To me, that seems to suggest that the additives will separate over time while the car is not being run. And if you get to 3 years and don't have 45000 miles, you car has been sitting a bit more. It seems reasonable to assume that the transmission will mix them every time it runs, but then why bother to shake it up before filling? Anyway maybe that has something to do with the time limit. (others have also suggested that the additives somehow just become less effective over time).
I have yet to tear off the skid plate and start this project myself, but I have read that there are 2 fill points. One inside the drivers rear wheel well, and another that is meant to be used for fluid changes. Where is the latter fill point?
The second fill point is actually used to add the extra 2 liter "track fill" to models prior to 2024. It is on the top of the DCT and you have to remove the trunk liner, interior trunk shell, and air intake box to get to it. Not needed unless you're adding the extra 2 liters and there is another way to do this fill if you're brave enough to lift one side of the car. Search YouTube for lots of videos.
For normal fills of the DCT you just use the fill plug on the side that you referenced - fill till the fluid is level - just starting to run back out.
The second fill point is actually used to add the extra 2 liter "track fill" to models prior to 2024. It is on the top of the DCT and you have to remove the trunk liner, interior trunk shell, and air intake box to get to it. Not needed unless you're adding the extra 2 liters and there is another way to do this fill if you're brave enough to lift one side of the car. Search YouTube for lots of videos.
For normal fills of the DCT you just use the fill plug on the side that you referenced - fill till the fluid is level - just starting to run back out.
got it. I’ve seen a dozen videos of the 2 L track fill, but only one on the fluid replacement and it breezed over the filling part. Thank you for the clarification.
Full Trans Fluid and Filter Change
