I’ve just read through some old CTC threads on replacing coolant, and see there are (or were then) some varied opinions amidst the consensus. My 96 Grand Caravan, which sat for about 5 years until I adopted it last month (running quite well now, thankfully) is obviously due for new coolant and hoses. What I read in the old threads coincides more or less with what I’ve done in the past…some variation of drain radiator / fill with water / run till hot / drain again / fill with straight coolant to attain a 50/50 mix.
Considering that I don’t know when the previous owner last changed the coolant, and especially considering that the engine didn’t run much for five years and not at all for three, do I need to do anything more than this somewhat standard exchange method? I have no burning desire to use chemicals or pay for a pro service. I do have one of those gizmos to hook up the garden hose for a flush, but that produces so much volume of liquid to take to our recycle facility…I’m reluctant, but willing if that’s what this situation needs.
Instead, I was wondering if there’s any benefit from a variation: drain / fill with water and drive a day or two / drain and add a gallon of green / and then drive it for a week or two / then repeat that a second time and replace hoses and thermostat. Or am I better off with the more conventional: two refills with water and only one dose of pure antifreeze, ending at 50/50? I don’t mind the cost of a second gallon if it’s some benefit in this situation, but certainly won’t bother if that’s just a waste of money.
Weird as it may seem, I like this car and am likely to keep it a while, so don’t mind a little extra effort to help overcome any issues that may exist after the long slumber. It’s a 3.3L V6, 152k, previous owner seemed to have maintained it fairly well.
Thanks for any thoughts!