Mention was made of keeping Adblue fresh, okay accept that is a good plan, but with many of our usage patterns, we don't keep piling on the miles fast to be refilling with fresh product.
Is the issue that "tired" Adblue is simply less effective, thus not doing a proper job environmentally, or is it actually harmful to the system?
Is it indeed drainable and is doing that desirable if we are not getting though a refill in say a year?