ASIDE from the above issues with the Bendix TreadlVac there is a common misconception that a 'modern' DUAL or Tandem master cylinder is safer. Perhaps true but only to a marginal or negligable degree is the tandem safer.

THERE IS a DANGEROUS down side to the tandem master cylinder espeicaly at very low speeds. This danger element is really only evident at very low speeds of say 5 mph or less. It can be experienced on very slippery roads dur to ice, heavy snow, moss covered creek beds, descending steep hills, loose gravel and other such low speed negotiations of peril.

The problem is that the rear wheel cylinders do not recieve equal pressure as the front wheel cylinders and what happens is that the rear wheels will tend to continue driving the car forward while the front wheels loose traction due to slippery surface.

NONETHELESS, i do not like the modern dual master cylinders either. For 56 and 55's (don't know about earlier Packards) the best bet is to use the 96'ish Ford explorer power unit and brake pedal assembly with a ranger master cylinder. Mount it thru the left fresh air vent hole in the fire wall. U will need 2WO of the F pedal assemblies and stop lite switch to make one. Cost it out at about $150. Pedal position will be about 1 inch higher than stock packard pedal.