It uses Dexcool.
5w30
Group 75.
Dex-cool it is orange-red incolor
The original coolant would have been "DexCool". The cooling system should be flushed and coolant replaced every 5 years or 100K miles if you use DexCool.
Any brand of antifreeze can be used in a 1998 Chevrolet Blazer. It is recommended that a person uses 50 50 antifreeze.
for my 2000 Chevy Venture I use DexCool. It is the ONLY one recommended by GM.
It depends on your climate but in most cases it would take 5W-30.
It uses the ORANGE coolant.
use a vortex coolant
R134a
use the handle....