Hi i have a question so i have a 1997 Ford F-250 5.4l i replaced all brake lines master cylinder and brakes and when i turn the truck on my brakes go the floor any answers for me plzz help me
Sounds like there may be air in the lines or in the master cylinder itself.
Some master cylinders you can buy pre-bled so you dont have to go through the trouble of bleeding the air out of them. I would try bleeding the brake lines first and if that doesn’t solve the problem then its most likely air in the master cylinder. I know Scotty has a video up on how to bleed your brakes you can check out. If that don't work I would see if you can exchange the master cylinder for a pre-bled one if available.
@riker67
OK but we bled them alot and its still Doing it its not my truck its my bf truck he said when the truck is off the brakes are hard the he said when the truck is on the brakes go the floor