Best Antifreeze coolant

You should decide on the concentration of anti-freeze and the type of additives (ex: sillicates protects aluminium but reduces the cooling efficiency).

As far as the concentration is concerned see previous thread on the subject : https://www.ferrarichat.com/forum/posts/146311585/
Bottom line is that you should read the 365 manual and follow the recommended percentage of water/glycol.

Regarding the type of additive you should be looking for, it also depends on where you live, and the type of water involved:

• https://gmb.net/blog/common-coolant-additives-explained/
  
• https://www.ferrarichat.com/forum/threads/coolant-types-and-levels.584202/#post-146190585

I presume all well known manufacturers are more or less equivalent and the best coolant among these manufacturers will always be a "fresh coolant". As far as I am concerned I was a loyal IGOL customer, but now prefer Motul products, because you just have an extensive line-up for trucks & motorbikes where they say exactly what is inside the bottles, also these products are easier to source (where I leave):

• During winter Motul HD Cool Tek Ultra (sold as 20l concentrate formula, does contain silicates) + demineralized water
  
• Rest of the year 5% Mocool (water wetter) + 95% demineralized water (that's 0% anti-freeze)
  
• This plus a new Calorstat RC0153 radiator cap (or Stant equivalent)

I trash the water and watter weter at the end of the season (that's ~30€ once factoring for the two bottles of Mocool and 4 bottles of demineralised water). I keep the diluted Cool Tek for two winters (so that's a 20l / 129€ barrel spent over 4~5 winters).

Last remark: some anti-freeze do leave some ugly stains during spill-over. Was a problem with Igol: took me ages to clear all these on the radiator and expansion tank.

(To answer your question: I was absolutely amazed by Mocool)

 

I assume you can use the following

ZEREX original green
ZEREX g05
ZEREX G48

Just doing a tiny research i would lean towards G48

I am new to the 400i but not new to Ferrari..i use G48 in my 512 TR ..

Sent from my moto g power using Tapatalk

 

There is a great discussion on the various Zerex products (https://www.ferrarichat.com/forum/threads/coolant-zerex-g48-sub-for-glycoshell.536909/#post-145025396), back then the silicate based Zerex seemed to be the way to go in order to protect the liners of our engines.

G-05 is specifically quoted (in the label) as suitable for our liners whereas G-48 may not be the most appropriate based on this small abstract from Xerex website:

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