Mazda Genuine Long life Green antifreeze. Call your local Mazda dealership.
The kind of antifreeze that is recommended for the 2004 Mazda Protege is the Genuine Mazda Long-life Coolant. You can also purchase Peak or Zerex coolants which are also considered compatible.
Mazda says to use their "Mazda Premium Gold", which they charge $18.00 a gal. The Ford Escape which is built at the same plant as the Mazda and Ford says to use their "Motorcraft Premium Gold" which is the same as that of Mazda and it cost$12.00 a gal. I use personally use Peak brand that mixes (blends) with all antifreeze, it does the job with no problems and cost between $8 - $10 a gal.
The 2006 Mazda MAZDA6 runs on regular unleaded.
The 2006 Mazda MAZDA5 runs on regular unleaded.
The 2006 Mazda MAZDA3 runs on regular unleaded.
Dexcool
50 / 50 mix of antifreeze and preferably distilled water Ford states not to exceed 60 % antifreeze in cold climates and not to use less than 40 % antifreeze for corrosion protection
Red HOAT type.
My mechanic told me they use Gold type antifreeze.
The 2006 Mazda MX-5-Miata runs on premium unleaded (required).
Red 5 year. Do not use Dexcool.