Hey guys so today my truck started.making this hissing noise coming from what it seems the vacuum booster, which is in front of the oil dipstick. Looks like an oil filter even. This would happen when I depress and release the brakes at idle or driving. Sometimes it may not happen but seems to happen every time. It just started today. Trucks has only 5500 miles on it. I'm sure it needs to be checked out but bad timing I have a camping trip to take the fam this easter break. As well as towing a 4000 lb travel trailer. Maybe someone can chime in let me know how serious would that be. Thanks. So frustrating. 
Pic shows what hisses
Pic shows what hisses
