So the question I have is I have a 1999 Dodge Ram 1500 5.2L and I went to pull the master cylinder off the brake booster and when I did it had a large amount of suction behind it. When you pull the master cylinder off and start the truck you can feel vacuum where the master cylinder passes into the brake booster is this normal should you feel vacuum their or no?

 

Do you brakes work properly?? (master cylinder issues aside....) If the answer is yes, think I would just leave it. If you have other issues, change it.