Ok so I just noticed that the coolent that I bought last might have been the wrong one!! I noticed as I used the last of it that while it said European and Range Rover it did not list Land Rover!!
went to the Auto Parts store and there was a Pink coolent that actually said Land Rover and gave the proper years, damn. Well should I drain the old out and replace!? Have I done any damage should I flush also?
While I have a little constant coolant lose is not very dramatic .
suggestions!! thanks in advance for your time.

 

You're probably fine. Long story short, most antifreeze additives are just various combinations of four compounds:

Silicates (Good for iron engines)
Phosphates (Good for aluminum engines)
Organic Acids (primarily Sebacic Acid)
2-EHA (which is an Organic Acid, but is important)

In Europe, they banned phosphates because they reacted with minerals in hard water to form scale on the engine. European coolant is therefore a combination of silicates and organic acids.

In Asia, they banned silicates because it interferes with heat transfer and wears away the water pump seal. Asian coolant is therefore a combination of phosphates and organic acids, or just organic acids.

GM made an antifreeze called Dex-Cool that contains only organic acids, including 2-EHA. However, this was found to cause problems for silicone, especially in head gaskets that weren't designed for Dex-Cool. There's also rumors (founded or not) of it mixing with air in the cooling system to form a sludge that blocks the radiator. To my knowledge, Dex-Cool and Dex-Cool approved coolants are the only coolant that has this. Ironically, this is the coolant your Discovery originally came with, and most people will swap this out.

I run Zerex G-05, which is designed for Mercedes, but you're generally fine running anything that isn't Dex-Cool. In honesty, the best choice is probably an Asian coolant mixed with distilled water (NEVER TAP), but I didn't really feel like risking it.

 

Here is an inside view of my radiator, which I replaced with a new one recently. I assume it is the original one ('04) and there is some sludge build up visible (intake side). Only the 2-3 lower channels were blocked. After installing a new radiator (Nissens) a small difference, about 3 degrees lower coolant temperature is noticeable. I also replaced all the hoses, flushed the block thoroughly and the radiator design itself could possibly make the difference. Also I don't know the exact history of my D2 (i got it at 102k), I know only that the PO had a blown head gasket, which could have been a cause for the sludge.





EDIT: Forgot to mention, that my D2 came with Dex-Cool and I continue to use that.

 

A few things:
- Coolants of different compositions should not be mixed. Corrosion inhibitor effectiveness can be reduced; some sources describe a jelly-like substance, which will clog small passages (like in a radiator), will form (which is what Discorama's pic appears to show).
- Don't assume the coolant in a used vehicle is of the type which came in it from the factory. Know what is in it, so that you buy a compatible, or the same, type. As Jason described, he switched from what came from the factory to a different type.
- Should you decide to switch from one type to another, thoroughly flush out the system with distilled water. This means expect to do it more than one time to ensure the old stuff is either removed or sufficiently diluted to the point of removing its ability to clash with the new, and different, coolant type.

For peace of mind, it may be worth it to flush and fill. You'll have to make the call.

 

this!!!!

 

First I want to thank everybody for the advise and guidance provided!