Just solve the problem by (....)
better to understand that the "problem" is being created by not understanding the system, just don't overfill the rad
I've never found a need for an overflow setup, although most years GM offered them as an option - but I believe every year
owners glovebox manual points out the level should not be "full",
especially with an antifreeze solution - it may be that eyell saying "
I am adding antifreeze about every 3 months" means there's a stronger then needed or useful concentration of antifreeze adding to the "problem" of overfilling
Bill
