Well pretty sure my vacuum pump is dying, just looking for some more sure diagnosis. Brake light has flickered since I got the truck, but brakes always felt great. Today, they started getting hard at idle. They are fine coming to a stop from speed, but if I then pump it a couple times, there's no boost. It slowly comes back, and if I get on the throttle it comes back faster( in park, I can pump the pedal till its hard, then Rev it a bit and fee it sink back down like it's building boost). Now, I just threw a serpentine belt after getting oil all over it (I need a funnel...), and replaced it with a house brand belt from O'Reilly. It was a bitch go get on, but didn't really seem to short or anything. I cleaned all the pulleys before putting the belt on, and it doesn't look like it was slipping. The pump felt good rotating by hand when the belt was off. I did also notice a decent amount of oil coming out the top of the pump. Is this a sign of failure? Is there any way to rebuild these things?