if your getting corrosion i'd say you have too much coolant in the system

ive used the nulon green concentrate for years and never had an issue.
i always mix in a little less than they reccomend just to be safe

i highly recomend toyota super long life red coolant to i use it in my 100 series landcruiser and had it in thier for 5 years drained it and not a single rust in radiator or in water!

use 50/50 ratio with distilled water!

The hardest thing with the old engine blocks is that you dont know the history of the block. There could be all sorts of scale waiting to come away regardless of the coolant you use. In a new car, using the good stuff from the word go will always give you the best results. (that 5 year stuff with the cruiser is entirely believable).

Unless you have had the block properly acid bathed and cleaned and scaled away, then there is no real way to assume that cause you are using a better coolant, you will get no problems.

Still thats no reason to not use the better stuff, just no guarentee that it will stop any problems.

Seems like the toyota stuff is the favourite.

Chuck that stuff in levey, or go the castrol if you are a tight A**E.

Thanks for the info guys, looks like I am now going for the Toyota red!
Colour wise it might clash with my blue transmition oil ;)

Mercedes coolant is blue, but $15 a litter or something. Get the Toyota one. I planed on it as I'm redoing one of my lines come summer and will put better coolant in too

Oh and nige lucky for you they are different colors, so at your age you don't top up with the wrong one.

On that point I let a person know at the servo they were about to fill their golf deisel with premium unleaded... I'm sure they could have givien me the $5k I just saved them lol

I like colour coordinated might go for the Mercedes coolant, $15/Lt is cheap compared to the $60/Lt I paid for transmition oil.