In a message dated 98-05-30 03:39:21 EDT, you write:

<<Lately my 1988 Double Cab requires me to pump my brake pedal once so it will
grab a little better.  If I push the pedal down on the first pump it will go
2/3 of the way down and it will softly stop the truck.  If I pump it again it
will only go 1/2 of the way down and I can stop much better. It is a bad
master cylinder, bad rear brakes or what?>>

1) Check the adjustment of your brake shoes on the rear.
2) Check the fluid level in your master cylinder.
3) Check for partial failure of master cylinder.