You may have a bad master cylinder, or proportioning valve,
Does the vehicle have Antilock Brakes (ABS) ? Please let me know.
Ben
No
If you are losing fluid and the pedal is low, you have a brake fluid leak.
The brake cylinder connects to both front and rear brake systems. The front and rear brakes are connected though a diagonal fluid distribution system. any more questions email me at philip.dharamraj@hotmail.com
Corrosion? Contaminated brake fluid?
have you checked your brake fluid??
yes , 1 chamber is for the front brakes and the other chamber is for the back brakes
Sounds like air in the brake lines or power steering fluid in the brake system instead of brake fluid.
Does this Blazer have four wheel disc Brakes? NEW ANSWER: There's no reason to bleed brakes if you did not open the system.( where brake fluid came out )
Sticking brake calipers. This can be caused by moisture in the brake fluid which will cause the calipers to rust. Replace the calibers and replace all the brake fluid. It can also be caused by driving with your foot on the brake.
it is possible that your brake hoses are bad and soft not letting the brake fluid back out of your calipers
Bad fluid in master cylinder,flush system,bleed brakes
Did you check the vacuum hose or did you refill the brake fluid?