I have a 98 Ram 1500 and when i hit the brakes the pedal goes all the way to the floor. It stops but not safely. I checked the reservoir and it was kinda full. Should I fill it to the top? There are no leaks around the truck either i saw in another post that it could be leaking into the wheel cylinders? I really need some help asap the truck is in danger of getting towed from where im at. Any advise would be greatly appreciated!!! Thanks.

Has there been any brake work done recently?
If not the master cylinder needs to be replaced imo. The piston inside is worn out.

i dont think so what youre sayin is probly right that was my next gess. its actually not my truck its my girlfriends. thanks for the advice