Roy Kruse 9/7/2010
1998 Chevrolet P30 Base 8 Cyl 7.4L
when stopping ,brake petal lost back pressure and and went almost to floor after setting for a day brake petal is normal
this is the only time this has happen. mieage on motorhome is 71300
You should check the brake fluid level in the master cylinder. If the fluid level is full, the master cylinder may need to be replaced.