Hey all, ive got a 93 f250 with a 7.5 4x4. Ive done calipers on vehicles before and have bled the system before as well. So i replaced both front calipers and went to bleed, took a long time and went through 3 big bottles of dot3 fluid and when i pump the brakes when the trucks off it becomes firm, the minite the truck fires up, it goes to the floor. I was stumped and took it to firestone and they said my brake booster wasnt creating vacuum. This is where it throws me off because im pretty sure the brake booster not working would mke a very firm petal not a soft one. Is it the master cylinder or is it really the brake booster that went bad? Im trying to sell the truck and just need it to work right.

 

You didn't install the calipers on the wrong sides? The bleeder valves should be at the top.

This seems to be a somewhat common mistake, and there is no way to get them properly bled if this happens. This may not be your problem, but thought I would throw it out as a possibility.

 

No they were installed properly i made sure of that. Im almost positive its the master cylinder but wanted to see what guys on here thought since its a little cheaper to get the bb and mc together instead of buying seperate. That way if i put it all back together and it really was the bb i dont get upset haha