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JimM68
Nov 17, 2015Explorer
This sounded so weird I felt a need to go searching.
What you have is called "hydro-Vac" brakes. The search phrase "Dodge Hydro-Vac" yields a lot of hits, including this one http://dave78chieftain.com/HydroVac_brakes.html
The system was used from 73 to 75, because a conventional vacuum booster was insufficient to get good rear braking.
Newer than 75, dodge went to a Hydroboost system, as used on many non-air medium duty trucks still today.
What you have is called "hydro-Vac" brakes. The search phrase "Dodge Hydro-Vac" yields a lot of hits, including this one http://dave78chieftain.com/HydroVac_brakes.html
The system was used from 73 to 75, because a conventional vacuum booster was insufficient to get good rear braking.
Newer than 75, dodge went to a Hydroboost system, as used on many non-air medium duty trucks still today.
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