[Zap]

Big question....PLEASE help!!!...1985 F-250 6.9l diesel. Auto. My brake light just started coming on, and my brakes have alot of resistance. I have to push with both feet to come to a slow stop....very hard to stop! I have had problems with the vacuum lines to the transmission, making it shift hard. I checked the vacuum hose going to the brake booster, and theres very little vacuum being created. Could this be the problem?...Any ways to check before replacing it? I just had $600 dollars worth of front brake calipers installed two months ago...thanks to all...

 

[jdc753]

Definetly sounds like a vacume issue I would think. Pete (cdnsarguy) has this test in his album Part 1 Part 2 Try that out, hopefully it will work for you and you can narrow down your problem.

 

[cdnsarguy]

This info just popped up on the 7.3 forum, it is well worth the reading time.

http://www.rockauto.com/ref/Cardone/vacpumpinfo.htm