Lots of aluminum bits on the 450SL and other much earlier MB engines dating to the 50's. Non-diesel heads were aluminum with various water pump/thermostat housing bits also made of aluminum. The mid 50's to early 60's 300SL had alloy blocks too as did the M189 engined 300SE from 1961-1967. The M130 engines from the late 60's to 70's tended to have numerous head related problems including corrosion but I'm not sure how much of the corrosion problems with those engines was due to poor cooling system maintenance or what. Mark

99% of cars made in the last 20 years have aluminum heads and the vast majority of cars in the last 10 years also have aluminum block. They all run on cheap green coolant. What makes Mercedes special?

2 things: most of us keep our MB's a long time, until things start to fail, and water pumps on MB's cost 3-4x your Ford Mustangs and Honda Accords.

Here's an interesting article on Mercedes antifreeze written by a Saab mechanic. I found this when I was researching the blown head gasket in my Saab 900 (before I owned Mercedes).

http://townsendimports.com/Web/cooling_system_folder/coolingsys.htm

You didn't read the link https://mbwholesaleparts.com/StarTuned/pdfs/AntiFreeDec04.pdf did you?

It's a matter of the Engineers designing the car to match the HOAT anti-freeze, as much as the anti-freeze matching the car.

It'll run just fine with other anti-freeze formulations, but it'll last longer with the right stuff.

You'll live a long time on a diet of Big Macs.

I see the exact same argument on the BMW and Volvo forums. All of them swear by the ultra special dealer coolant because they have aluminum cyl head or aluminum block. Read the back label of your nearest Prestone bottle. You see the words 'aluminum safe' somewhere in there. And no, you don't drive your Mercedes more than the average honda or toyota driver. In fact I'm willing to bet there are a lot more 300k+ mile hondas on the road than Mercedes. But if it helps you sleep better at night knowing that you have Mercedes branded coolant in your engine more power to you. I'll be sure to let you know when my cheap green walmart coolant causes an engine failure.

?
http://www.********.com/catalog/raframecatalog.php?catalog=201&partnum=571351&a=FR201-571351

"aluminum safe". Sure, that means a lot if all I'm worried about is aluminum. I'm guessing you're not an Engineer or a Chemist, ... and BTW Mercedes also mentions in that article: "<snip>the Mercedes-Benz
recommended hybrid type? If you buy your
anti-freeze from an aftermarket source, use a
reputable brand that meets current Mercedes-
Benz formulation, typically labeled a G-05
coolant."

No problem with aftermarket, as long as it is G-05, I haven't bought a jug from a dealer in a decade since I can buy the Zerex G-05 a mile away.

There are many properties to a coolant beyond simply protecting aluminum from electro-galvanic corrosion, consider cavitation pitting for example.

I'm sure you are an Engineer or a Chemist and you know a lot more about coolant than I do, no argument there. I'll stick to the cheap stuff just like every other too cheap to know any better 15+ year old Mercedes driver (i change it every 2 years). You can use whatever you think is best. When my engine fails you'll be the first one to hear about it.:D

Like I said: you can live a long time on Big Macs and soda, doesn't prove much.

Your engine will likely be fine on Prestone or whatever, at 15+ years old if it has been maintained fairly well, something else will likely kill it first. I don't mean to sound like there's some higher power that has sent down coolant specs on stone tablets and we'll all be condemned to U-pick yard servitude if we don't comply, just that there is at least some logic and chemistry to the use of one coolant vs another. Look at GM and their recommendations of deathcool, that worked out well ROFL.

I also run my Cat on Cat coolant and extenders, just easier IMO to go with the OE or OE-spec products than to spend lots of time researching what is equivalent.

Coolant thread - the new oil thread.

So it would seem. Mark