Went to move the truck and pedal went to the floor, brake and abs light came on. Barely any brakes. No obvious fluid leak or loss. This morning, went to move it to the garage, and pedal is back to normal, and lights are off. I'll check lines and look carefully for leaks, but am puzzled as to why today it seems to be working fine. Any thoughts?

 

Brake is assisted by a Brake booster that runs off a vac line. It's possible you have a small vac leak in the brake line.

Did the truck sit for a long time before you initially moved it? a fluid pressure regulator could also be out that allowed brake fluid to flow back, that would most likely be a problem in the brake master cylinder.

 

It sat for about a week. I thought about the vac leak, and have some suspicions about that as well. Thanks- good thoughts.