1990 300SE cooling system questions

My 300SE has experienced the failure of its radiator's plastic neck so I will have to replace it and am ordering parts.
Questions:
1) What is the correct thermostat - 87 or 79 degrees? It is the auto
transmission model with A/C.
2) Mercedes recommend using its own antifreeze because of corrosion concerns. Are there acceptable alternatives that are available at the ordinary autoparts store?
3) Is this a simple unbolt & replace activity? I have done basic repairs over many years but have not replaced a radiator that has an ATF cooling connection like this one apparently does.
Thanks for any tips.
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87 degree is standard thermostat. I suggest you stick with MB coolant... they are far superior than the normal green stuff and far superior to that nasty dexcool.
Simply replacement.
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What evidence is there that the MB coolant is so superior? I've yet to see a modern car using either std coolant or dexcool have any failures which could be indentified as coolant related.
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On 2004-08-13 23:02:26 -0700, snipped-for-privacy@optonline.net (Chet Hayes) said:

I agree and many pro mechanics I have spoken to open laugh at the concept of "mercedes coolant".
Although some of them also laugh at mobil 1 and I swear by that stuff.
Use your own judgement, but I am running regular old green generic antifreeze in my MB.
Marty
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As with any coolant, you must replace it every 2 years. The reason is any water contact with metal... will create acid... so over a long time... it will start to eat your gaskets... metals.. etc. This is why you see coolant related problems.
Mechanic don't tell you this or even think about it because they want business for repairing big stuff that cost you $$$.
As for MB coolant being superior... that's because I read reports on composition and how they are formulated. The green stuff has qiute alot of silica... it is a necessary component of coolant protection... However, the coolant is set to be alkaline... alkaline is not good for engine either... but okay... Anyway, so as the coolant gets old... it goes from alkaline toward neutral to acidic.
MB coolant is much less silica... which is better for aluminum engine... and the coolant is buffered base... meaning it is formulated at near neutral pH level... the pH remains at that level until it is exhausted and then it goes toward acidic pH.
So technically, MB coolant is superior because it protects the engine by having the pH remains near neutral for far longer time before it is exhausted...
Whereas the green stuff is caustic either way and does not stay at near neutral for long because it is like your fuel gauge... goes from alkaline to acidic as you empty your gas tank.
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Thanks to all for the responses.
I will check out the Zerex G05 coolant as it seems to be a MBZ approved alternative to their own brand.

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Easiest place to get is at the dealer... but if you are ordering your parts online... buy a gallon or two just in case... about $10 a gallon.
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Saw some Zerex G05 (which meets MBZ quality specs) at Autozone for $9/gal so will probably go with that.
Thanks for the tip.

parts
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