Autobahn Blue anti-freeze needs a replacement

[Al S]

I am sure this has been brought up before, but is there a cheaper
replacement for ol’ blue that gives as good or better protection.
I know there are some good no-phosphate anti-freezes out there.
It is time to replace my coolant and I went to the dealer yesterday,
thinking it was going to cost me the $11.00 USD that I spent a couple of
years ago. NOT!!!, $18.00 USD. Talk about sticker shock. This isn’t oil, is
it?
Please there must be a coolant that could replace ol’ blue.
Question #2,
  Do I need to use a special flush?

Thanks,
Al Streicher
Rathdrum, ID.

1990 80 non-q 180K