Recently purchased a 95 7.3 w/157k miles. The truck had green coolant and a new water pump installed just before i bought it. I have unlimited amounts of green antifreeze available to me but want to make sure im not setting myself up for trouble later. Should i go with cat elc or the other elc's mentioned for my obs? Id rather not have to worry about the sca maintenance, but didnt know if having tons of free green coolant would be ok to keep fresh in there instead of the high dollar elc? I also noticed that i dont have any coolant leaks visible in the driveway but seem to always need to add 1/2'gallon of coolant to overflow tank, it doesnt smoke white while running, only a blueish that fades away after warmup..anynideas where it could be going? And lastly, a coolant filter? Is it necessary/overkill/or just a good idea ? Im new to the diesel world and full of questions and dont want to blow a bunch of money if not necessary.