I noticed 2 days ago my brake pedal goes hard when I shut my truck off. Everything works fine once I start it up. Just sucks when parked on a hill and push clutch in the start the truck and it rolls back because i cant push my brake down. I've read it could be the booster check valve I've tried to remove it to see if it's working properly but I cannot get it out of the booster. So any tips?? Or other ideas on why this is happening. It did it a year ago and when I got my front caliper replaced it never happened again till the other day. Thanks guys. It's a 2009 4x4 4.0l has 120000kms on it

 

Yes, could be check valve, it just pulls out but a very tight fit

And could be the booster itself is leaking

Pull off the engine/intake end of the booster's vacuum hose and suck on it, it should hold vacuum, negative pressure, if not then booster is bad not check valve


Yes, booster is so large so it can hold enough vacuum in reserve for 2 or 3 emergency stops if engine should stall while driving, so you should have vacuum assist for 2 or 3 pedal pushes after engine is off

 

thanks I'll give it a try. Hope it's just the valve booster looks like a shitty job to do myself. Thank you