Packard Forum Index » V-8 (1955-56)

My brake light switch only turned the brake lights on if I stood hard on the pedal. Like...put yourself through the windshield level of hard braking. That's not good.

I'm a career auto parts man, and I searched through every catalog I have going back to the 1970's, and none had the 3-pin brake light switch for Torsion-Level cars, It appears this switch was made by Casco for Packard for only two years, and was never produced or sold aftermarket.

I bought a NOS switch from a Packard part supplier for $130. It didn't turn the brake lights on at all, and began leaking fluid from the crimp on the switch body after about the second pedal press.

A second $130 NOS switch did exactly the same thing. Both switches were leaking black goop out the threaded end after I removed them. My guess is there is a rubber diaphragm inside that is rotten after 68 years of sitting on the shelf and that black goop is the rubber disintegrating.

Many of you have heard of the 1970's Volkswagen switch (NAPA # SL159) that uses slide terminals instead of pin terminals. I bought one and it threads into the T-fitting on the frame rail perfectly. I created an adapter harness that plugs into the original Packard connector with individual pins, and to the Volkswagen switch using a Napa # EC428 connector.

The original Packard harness has three wires:

Pink: Power feed from the fuse panel. Hot at all times.

Light Green: to Torsion Level.

Dark Green: to brake lights.

If you are looking at the top of the Volkswagen switch, rotate the switch until the terminals are at the 3:00, 6:00, and 9:00 positions. Connect the pink wire to the 9:00 terminal, the light green wire to the 6:00 terminal, and the dark green wire to the 3:00 terminal.

The Volkswagen switch is very sensitive. It turns on at about 100 PSI. I did some testing on the vehicle and found that the brake lights come on just before the brakes begin to engage. However, I have had zero problems with the switch staying on after the pedal is released.

Napa's Echlin brand was one of the last to make the 3-pin switches but stopped some years ago. I can well imagine that an NOS brake light switch wouldn't last for the very reason you mentioned. I have one of the later Echlin ones to try in my 1956 Clipper once I get to the brakes but I've been keeping the Volkswagen switch in mind in case it doesn't work out, especially as my preference is silicone brake fluid. I've heard that many of the VW switches have a fast failure rate but maybe there are higher-end ones made for synthetic that will last longer.

The VW switch has been used by several others but reports of it having a fairly short life also are an issue -- just like the original switches, reports are more for cars using silicone fluid -- but apparently failures of the VW switch have also been noted with the ordinary glycol fluid.

Wells is another mfg who made a three terminal configuration switch that is still found occasionally. I believe Standard also makes one but either of those may be the VW or Napa version with the reportedly short life.

There is a two terminal hydraulic switch and relay conversion that seems to work for most but others have noted issues with Napa switches and suggest using a Harley Davidson 2 terminal switch that apparently is made for silicone fluid. Not sure who sells that conversion now since the Northwest Packard region did not show it on their website last time I looked. About the only other proven 3 terminal alternative that seems to have a decent life is the conversion to a mechanical switch operated by the brake pedal arm. If your just replaced hydraulic switch gives up again you might consider changing to mechanical.

Dwight Heinmuller has mechanical kits that mount to the steering column for both the 55 and 56 power brake pedal arms. If the car has standard brakes then a mechanical 2 terminal switch mounted under the floorboard and operated by the pedal along with a relay conversion for the third terminal would be the option.

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Ron Francis also make a 2 prong switch that is supposedly compatible with Dot 5.

I'm using this

After market low pressure switch
.
And so far no problems.. For silicone...

From what I read. Low pressure is for silicone..

Lightly touch pedal lights go on. When power off

And energizes my relay.

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Quote:

Do you have a brand, application, or part #?

It's the Harley-Davidson switch.

I'll have to look at package

Its an after market for a Harley.

Had to search by number think Harley part number

Visit the Billet Proof Designs Store
Goodridge Male 1/8" NPT Brake Light Pressure Switch - Replaces Harley Part# 72023-51D - Tested to 1 Million Cycles

On amazon..


Goodridge Male 1/8" NPT Brake Light Pressure Switch - Replaces Harley Part# 72023-51D - Tested to 1 Million Cyclesa.co/d/bB0w9Hw

I would love a wiring Diagram of using the two pin switch with a relay for the TL. Wiring relays are not my strong suit.

Here is an easy to make relay setup using a readily available 12v Bosch style cube relay that can be found at most local parts stores, Amazon, or Ebay. The brake switch is from Napa or an equivalent can be bought at most other parts stores. (Note that if you use silicone fluid, some have had issues with longevity on the Napa switch and the Harley Davidson switch may work more reliably but to date there is not a lot of history to support that as fact.)

You can make an easy to connect wire harness with terminals and wires also found at the same places. Length of wires to suit where and how you mount the relay.

If you want to completely eliminate any issues from the hydraulic switches no matter which brake fluid is used Dwight Heinmuller sells a mechanical switch kit for both 55 and 56 models that mounts to the steering column inside the car and is actuated by the brake pedal arm.

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