Thanks swoop.. I will post back with my findings

the secondary relief valve (located on the end housing of the control valve) may be damaged.
pressure test port is located on the main lift valve section, hook a 3000psi guage to it and then operate the tilt in a stall mode and take a pressure reading. it should read about 2250psi.

if it does not then you have an issue with the flow regulator (secondary relief valve) for auxillary pressure.

this would be my first guess since it is affecting all the auxillary functions and steering.

D187V30400A
GM engine

Serial number of truck??