2x Coolant??
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Joined: Feb 2021
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Audi A6
2x Coolant??
I got a low coolant light so went to check the reservoir and it was super low. When I went to close the cap I noticed (under the engine cap) there’s a 2nd reservoir and that seemed full… I took off the engine cover and the 2nd cap indicated that it was also a coolant reservoir (just smaller and it had the same coolant)
Can someone confirm that there is 2 reservoirs and what is the purpose of the 2nd one (maybe for the turbos or backup?)
Also I couldn’t find the marking to fill to on the side of the MAIN reservoir is someone can help by chance.
Thanks Gents
Can someone confirm that there is 2 reservoirs and what is the purpose of the 2nd one (maybe for the turbos or backup?)
Also I couldn’t find the marking to fill to on the side of the MAIN reservoir is someone can help by chance.
Thanks Gents
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2015 C400 4MATIC Palladium Silver Metallic
The smaller reservoir is for the Intercooler and Transmission cooler.
If you look straight down through the fill hole, there's a plastic "T," the coolant should just cover the "T."
If you look straight down through the fill hole, there's a plastic "T," the coolant should just cover the "T."
Last edited by TwoC400s; Sep 24, 2024 at 08:48 PM.
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2018 Mercedes C43 AMG Coupe
To add to that, engine coolant (main circuit coolant reservoir) feeds the turbochargers -- it uses the same circuit as the engine. Whereas the low temperature circuit coolant reservoir feeds the intercooler and trans cooler as stated.
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C43 AMG '17 / Stage II
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From: Los Angeles, CA
2019 S63 AMG (Current), 2015 E63S, 2008 E63, 2005 E55
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2018 Mercedes C43 AMG Coupe
I have a 2019 S63 Sedan. My car has two reservoirs. Today I found out that the center engine reservoir was low and my transmission temperature was rising. Just want to verify that the main reservoir cools the engine and turbos and the under engine cap reservoir is for intercooler and tranny? The small reservoir doesn't cool the turbos at all even though it's right next to it?
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From: Los Angeles, CA
2019 S63 AMG (Current), 2015 E63S, 2008 E63, 2005 E55
my tranny got to 250F levels. Didn't enter freeway, drove only 1.5d realized temp rising and then took it to dealership. I had brief spike to 250f. Do you think our tranny is strong enough to withstand it for a bit? Kind of freaking out tbh. No sensors and no fault codes found.
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Joined: Nov 2017
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2018 Mercedes C43 AMG Coupe
my tranny got to 250F levels. Didn't enter freeway, drove only 1.5d realized temp rising and then took it to dealership. I had brief spike to 250f. Do you think our tranny is strong enough to withstand it for a bit? Kind of freaking out tbh. No sensors and no fault codes found.
Super Member
Joined: Jun 2014
Posts: 517
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From: Los Angeles, CA
2019 S63 AMG (Current), 2015 E63S, 2008 E63, 2005 E55
Yeah lol, wanted to continue here instead of new thread. Shifting is fine, no issues, no fault codes, nothing, just barely went up to 250f then cooled for a bit then dealer. Turbo reservoir was low / empty.
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MBWorld God!
Joined: Dec 2019
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Super Member
Joined: Jun 2014
Posts: 517
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From: Los Angeles, CA
2019 S63 AMG (Current), 2015 E63S, 2008 E63, 2005 E55
asked to look at tranny mounts as well, no eta. So in the past month or two, rear main seal, oil separators, bearing/pulley, engine mounts, sway bar link, coolant lines, oil change, tranny oil change, coolant top up, also my entire passanger side suspension, car felt so refreshed. About 25k in work. Knock on wood.
MBWorld God!
Joined: Dec 2019
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asked to look at tranny mounts as well, no eta. So in the past month or two, rear main seal, oil separators, bearing/pulley, engine mounts, sway bar link, coolant lines, oil change, tranny oil change, coolant top up, also my entire passanger side suspension, car felt so refreshed. About 25k in work. Knock on wood.
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From: Toronto
2022 E53 AMG
To flush the coolant, I take my car to MB as I don't care about the cost as I just want it done correctly. If you are loosing coolant after you have refiled it multiple times, it's time to check the cooling system for a leak.
