Archived brake booster/vacuum? HELP

[turbinesurgun]

about a week ago my driver was having problems with power steering at low rpm and now he is having the same problem with the brakes. What is this thing behind master cylinder? What does it do? It is connected to both power steering and brakes right? The truck is a 2003 dodge 3500 2wd six speed. I just believe this thing is the problem because both systems connect here any help greatly appreciated

 

[Missouri Mule]

I believe you are talking about the Power brake booster. I"m not sure if use vacuum or power steering fluid to work it but in 97 they went to power steering fluid to work it so I would assume they did not go back to vacuum in the third gen trucks.

You will have to check out your power steering pump/components and the brake booster to see which one is causing the problems.