All non-green coolants are similar in that they use no or very low levels of silicates. Silicates are the mainstay of green coolants and coat the metal surfaces to provide protection, but comes off after a few years. The flakes are abrasive jelly-like clouds that wear the ceramic face seals of the water pump and eventually cause a leak. This is why you are supposed to replace it frequently. Taxi fleet testing by Texaco showed that water pump failures in the first 100,000 miles/14 months (typical 24/7 taxi service) went from hundreds to nearly zero.
Here are some pictures of it:
http://forums.viperclub.org/rt-10-g...-you-curious-how-dex-cool-performs-viper.html
The red, orange, yellow, etc coolants use organic compounds that only attack corrosion sites, so a) it does not induce a heat transfer barrier layer, b) is available for a longer time because it isn't used up right away. If you want to ensure better heat transfer (and after all the hoo-ha about thermostats, fans, etc, this probably includes everybody) then why put down a layer of paint inside the cooling passage? Think about it this way, the additive in green coolant is fully depleted after a month - it can't recover and prevent corrosion in a new part or new spot.
The OEMs have their individual opinions about the need for very low levels of silicates for certain situations or slight variations of the new chemistry. Despite this, the aftermarket has found formulations that meet all their requirements simultaneously. My consulting company recently evaluated magnesium corrosion protection (as the absolute most difficult material to protect) and Peak Global Lifetime coolant did very well. (I get no benefit from advocating this product.)
I've used preproduction versions of Dexcool ('92 van with 318) for one charge until I traded it in in 2005, then Dexcool or other OAT coolants in every car I have.
Roe recommended it for my Gen2 with a couple bottles of Redline Water Wetter.
