The brakes on my '98 K3500 have always been fair. Last year the power steering pump started acting up and I replaced it. All has been well until today. Took the truck to the end of the drive and the pedal went to the floor. I was able to stop it by putting my leg into it - loss of boost? Not losing any fluid. Steering is fine so I doubt there is a problem with the pressure to the brake assist. Pedal also goes to the floor when the engine is off. I don't think this is normal, but not sure.
Is it a loss of the brake assist unit behind the master cylinder, loss of the master cylinder or a problem with the antilock braking? What checks are there?
It's fair week so I have to get this thing back on the road fast or deal with an unhappy daughter and wife - help!
Thanks,
russfixr