Problem here is having to answer the question is this a Power Brake problem or a Power Steering problem.
Did you properly fill and excersize the system?
A. Fill Power Steering reservoir to the proper level and let oil set undisturbed for several minutes.
B. Start Engine and run momentarily. Stop engine.
C. Add more oil if necessary.
D. Repeat steps B. and C. until oil level remains constant after running engine.
E. Raise front of vehicle until wheels are off the ground.
F. Turn wheels back and forth from stop to stop (lightly contacting wheel stops)
G. Add more oil if necessary.
H. Lower vehicle.
I. Start engine and depress the brake pedal several times while rotating the steering wheel from stop to stop.
J. Turn engine off and then pump brake pedal 4-5 times to deplete hydroboost accumulator pressure.
K. Add more oil if necessary.
L. If oil in reservoir is foamy, allow vehicle to stand a few minutes with engine off then repeat the above procedure.
Warning - Operating the pump with foamy or milky looking fluid (air in the mixture) can damage the pump and/or hydroboost pilot valve.
BEFORE DRIVING THE RIG
Once the system is properly bleed, then you check all components for leaks (Power Steering pump, steering box, hydroboost unit, hoses).
Are all hoses in their appropriate location?
You now want to see if you hear abnormal noises from either the steering gear or hydroboost unit.
There are common fluid noises with this type of system.
A. When wheels are fully turned to the stops you will get a moaning noise. IT IS NOT RECOMMENDED TO HOLD THE WHEEL IN FULLY TURNED STOP LOCK POSITION FOR MORE THAN 5 SECONDS.
B. If the pedal is fully depressed there will be a faucet like noise (engine running). This is an abnormal pedal state. Emergency braking only or with vehicle stopped and pedal fully depressed.
C. If the engine is off and you depress the pedal therby using the stored accumulator energy, there will ba a hissing sound.
D. If the accumulator is drained, then an additional hissing will be heard when you start the engine as the accumulator is recharging especially during the first braking manuver.
That is a start. The point being to isolate the problem to either the steering or hydroboost unit. Both units will whine if there is low fluid level.
Here is a web site with information that may help you isolate your issue: http://www.brakeandfrontend.com/Arti...t_systems.aspx