83 GMC 4X4 power steering and power brakes issuse

[TRASH_PANDA]

Hey y’all new to the 6.2L world having some issues with the truck and need help so power steering and brakes only work for the first 5 sec after firing it up the brakes sometimes longer I replaced the fluid and belts still nothing thanks in advance

[DmaxMaverick]

Welcome aboard!

Is this a "new" problem? Or did it only start after the fluid change? Air in the system will cause issues with the hydroboost unit pressure regulation, and takes a while to bleed out all of it. Symptoms should improve while it bleeds, but it can be intermittent in the meanwhile. A hard stand on the brake pedal should strain the system. You should hear fluid passage, and feel it in the pedal. The pedal resistance should increase, but will go all the way if you stand on it hard enough (should be a lot of feel and squeal, if you do). The pump should also strain. If nothing happens, or the pedal just stops hard before about mid-stroke, read on....

You've eliminated the simple stuff, and you can also count out the steering gear box. That leaves the pump or the hydroboost unit, and it could be either. I suggest looking for the most leaks, and start there. Probably the HB unit, though.