Hey everyone! Last night, my boyfriend and I were towing one of our buddies trucks home after his motor blew. On the way back to our buddies house, my boyfriends power steering shit the bed and he lost pretty much all brakes and power steering. We filled the PS pump with fluid at his house, but...

New to this, but I’m a standstill.. had it looked at by a diesel mechanic and he said it’s the p/s pump, so here’s the problem when in the lower rpms driving or stopped if I press the brake or turn the wheels I get this bad grinding sound and a lot of vibration... the whole master cylinder...