Reginald P. Smithers III wrote:
BAR wrote:
Tim wrote:
On Dec 27, 8:58 pm, BAR wrote:
Eisboch wrote:
"Short Wave Sportfishing" wrote in message
...
When I talked to the Service Manager, he mentioned something about
losing vacuum pressure. I said what? I'm trying to figure that one
out - brakes shouldn't be controlled by vacuum pressure - I always
thought they ran off the power steering assist pump.
It's not "vacuum pressure", but doesn't the power brake system
operate off
of engine vacuum? I haven't checked new vehicles but I think the
older ones
did.
The newer ones do run off of vacuum pressure.

Off a vacuum pump.

No pump, vacuum from the intake manifold is the source.


Doesn't the transmission also use vacuum pressure in some manner?


On some Ford transmissions it does. I had a C4 transmission that had the
modulator valve's diaphragm rupture and start sucking transmission fluid
into the intake manifold which produced a dense cloud of white smoke
behind me as I drove down the Interstate. Seven dollar part, back in the
day, and it could have ruined my transmission if I had kept driving.