steh-fan

I was wondering which is the correct ACS fluid to use and whether there is a good write-up how to change the fluid (besides just replace what is in the reservoir...).

Thanks!

rapidoxidation

ADS fluid?
does that go in the reservoir next to the blinker fluid?

steh-fan

That is absolutely correct!
Where the circle is is for ACS fluid, and where the arrow is is where the blinker fluid gets in.
The blinkers will give a nice new shine when you add it there!






P.S. I corrected my typo! Sorry for that.

BlownV8

I believe active curve uses Pentosin CHF 11s. You have it on your 450? If you are having to add it, there must be a leak or are you changing it?

steh-fan

Thanks, that's what I thought. I heard it's quite a bit. I don't have it on the 450, but I'll changing to a 550 that alphas ACS and the off-road package (along with some other cool options).

I just thought to replace the fluid as it probably has never been done.

BlownV8

I'm not really following you. So, you do not have active curve but you are thinking of changing the active curve fluid in a 550 you are looking at buying?

What do you mean you heard it's quite a bit?

Can you explain? "changing to a 550 that alphas ACS and the off-road package"

steh-fan

Hi,
you're right, I'm getting rid of the 450 and will purchase a 550 that has ACS.
I read somewhere that it takes 11 quarts hydraulic fluid to fully replace.
But so far, I have not yet found the recommended service interval and a description of the procedure.

Thanks for the help!

BlownV8

That's because MB probably lists it as a lifetime fluid which means the max time they will warranty the car. It will spring a leak before or around 100k miles and the repair is not cheap. The system does work well but, if you want a more reliable vehicle, I advise against the option. Again, it does well at keeping the big girl relatively flat around curves, but you are in a huge SUV so there's that.

steh-fan

What on these vehicles isn't expensive to repair - with a $900 transmission fluid change and a $800 second key option ..... 😉
Any ideas where these leaks typically occur by chance?
Anyways, good I have an extended warranty (hopefully one that actually pays &#128516....

BlownV8

The pump can fail and leak.

You have an extended warranty on your 450 or the 550 you are thinking about getting? Good luck finding a warranty company who will pay. If you have one that has paid a big claim, let everyone know. At one time, there were some really good ones out there, but they learned their lessons and no longer write MB.

steh-fan

I currently have one on the 450, but that warranty has a labor rate cap that I wasn't aware of.
They did pay out every single claim (and the last one included an engine harness replacement), but as you can imagine, I was not happy with the amount.

For the 550, I purchased a new one, but it's t early to tell whether they are good or not.

BlownV8

So, you did purchase a 550 with active curve? Sorry, it's me not you, I'm confused.

steh-fan

Hi,

Yes, that is correct.