I have a strange brake issue that started about a week ago.

When driving slow (maybe 20 MPH or so) and applying the brakes the brake pedal is pulled to the floor and the truck comes to a complete stop on it's own. It has only happened three times so I am not sure what exactly happens to release them, but it seems that my pulling up on the brake pedal caused the brakes to release.

I would think the problem is in the master cylinder or booster, but I don't want to throw parts at it hoping they are the problem. I have plenty of experience with car type brakes but no real experience with Hydroboost.

Does anyone know what would cause the problem I have described.

Thanks

 

What year is your truck?
Does it have rear discs or drums?

Even a small oil leak on drum brakes can cause them to stick.