Front Brake Problem

Replaced the flex hoses on my 90MJ and flushed the brake system,the old brake fluid was black and had never been changed. Went for a test drive and several miles from home my front brakes started dragging and would not release, drove home at 5000 RPM going 20 MPH. The front wheels were so hot it melted the trim rings and it was at least an hour before the wheels were cool enough to remove. Replaced the calipers which were just fried and put new shoes on,flushed front brakes and all works well. BUT what would cause my front calipers to both start dragging at the same time??

When you put on the new pads, you pushed the caliper pistons back into rusty bores in the caliper. The rust made the pistons stick in the bores.

The moral of the story here: change your brake fluid every year or two, so as to prevent rust inside the brake system.

Brake fluild is an alcohol, and it absorbs moisture like all get out. Once the moisture is in the system, it starts attacking the steel and iron parts of the brake system.

True,however I relaced the brake flex hoses,flushed the system then went for a drive which is when the problem happened. I replace the calipers and pads after I fried the origional ones. The problem you describe usually only affects one caliper not both at the same time. Also used a vacum bleeder so as to not over extend the master cylinder piston, there is also some free play in the pedal so I don't think the compensating port is plugged. Still can't figure out what happened. Comments are appreciated.