I have a 70 Chevelle with power brakes. The brakes are just as hard when the engine is off as they are with it running. Is my booster bad? What years are the same?

Check to make sure your vacuum lines are all connected and tight. As for compatability any GM A body 68-72 should be the same. You could also pick up a new replacement or have your original rebuilt.

Lines are all tight. Who can rebuild the boosters?

I haven't used them but I hear good things about these guys www.brakeboosters.com (http://www.brakeboosters.com)

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