Here's what ethylene glycol mixed with mineral water can do to aluminum after not being changed in 14 years in a car with only 2,000 that was all new. Only ate the tank nipple and only clogged the offset in the t and never leaked or over heated. The T was open straight to allow the coolant to flow fine. Battery was replaced after 10 years and it was fine. Lol

I should add that despite it looking perfectly green with 0 rust when drained it tested as having 0 protection.