[Jrainman]

I have looked in to this a few years back, I am a old timer like most of us we came from the Copper era rad , when you could throw just about any type of water or antifreeze in your cooling system and forget about it , Not today, the thin aluminium is very sesaptable to this problem , today you must put a quality antifreeze in you system and if any water is to be added it must be a distilled water, I personly use only BMW coolant they have been addresing this issue for years and have a very good formula that addresses this issue , yes its BMW expensive but it work ,if you ever owned a BMW then you know how delicate there cooling systems are , let me put it this way, the saying in BMW world is if one cooling part fails even a hose , replace everything,, and everything is 4 times as many parts you see in a American built cooling system.

here is the test you must preform if you have a aluminium rad, take a voltage reading , anything over 0.10 volt will cause eletrolysis effect ,

this is how you check take a volt/ohm meter take positive lead and stick it in your radiator make sure its only touching the fluid

first check is neg ro rad support read meter then neg to engine read meter then neg to frame read meter after that have someone sit in the cab put ignition to on, keep your neg to frame , I like to use the engine to frame ground wire , then have that person turn on every electrical acc you have on one by one radio, lights , brake light, horn,etc etc. and watch the meter when you find high volt spikes these will be the problem areas that are giving you your issues