[V8] coolant

[Kneale Brownson]

Just like the recent oils thread, why would you use something other than what Audi specified for its cooling systems?  I purchase Autobahn brand phosphate-free blue coolant from the dealer.  It costs half again as much as the standard green crap from FLAPS.  Not much of an additional expense (considering the cost of fuel today) for something you use a gallon or so of every two-three years.  I buy several gallons at a time (five operable Audis in the yard) and always carry some in each trunk.  It is completely compatible with the green stuff in an emergency.

d saad <dsaad at icehouse.net> wrote:  

I was using Zerex 5-year orange coolant. I think it is similar to
"dex-cool".
The inside of my motor looks fine - no scale or
buildup or corrosion, and the radiator is also still good, and not plugged
up at 150K miles. However, I began to wonder why the head gasket failed
the way it did.