I'm in Springfield, MO. The weather has been below freezing for a few days and we had snow yesterday early. I drove without an issue yesterday in the slush. Coming home yesterday evening the temp was 17, no issues. Last night it was around 6, and when I went out to leave this morning, I had a hard brake pedal, like manual brakes. I thought maybe water in the lines froze so I bled the brakes without a problem. No change. I drove a mile down the road riding the brakes to heat them up and then back to the house and no change. I moved here from FL roughly 1 1/2 yrs ago so not used to these type of issues.

I guess I need to check the vacuum to make sure nothing is frozen there, don't know why it would be but worth a look. Any other suggestions? Thanks in advance for any help.

 

Make sure that the vacuum check valve didn't go out. It's the one that is on the brake booster and has the hose going to the intake. When the go out the brakes will get real hard. Just something else for you to check.

 

At those temps you aren't going to bleed out any water that might have been in there - it's ice now.

You might try grabbing a hair dryer and warming different parts of your brake system, one at a time, to see if you can clear the problem. If warming one part makes things work properly, you at least know where the problem is.

 

Are the brake adjuster rubber plugs missing from the rear brakes??? Might you have gotten slush into the brake drum that froze overnight ??? Also, do you change your brake fluid at regular intervals ??? I'm thinking the return port within the master cylinder may be blocked and not allowing the complete releasing of the brakes...

 

Found it, the vacuum check valve on the booster had fallen apart. Not sure why, was working fine with no issues and then done. It had fallen apart and had a split in the side. I guess I assumed it was related to the cold weather, only my 2nd winter here.
Thanks for all the advise, I love the help I get from the forum.