Can anyone tell me what this is??

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VPC20HD

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Can anyone tell me what this is??

Thank You!
 

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legopnuematic

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Trailer brake controller.
 

brooksman9

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Several years ago I bought a 72 Camaro. Had some kind of sensor under the body and something on the drive shaft that triggered it every rotation. Found out it was some kind of aftermarket cruise control apparatus. I think someone told me they came from Sears when I posted pics of it on NastyZ28. I don't remember there being anything inside the car for it though. Just speaking of odd old things.

Ha! Even found the post from 2007. :p

 
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PrairieDrifter

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Looks like the Kelsey hayes unit I just picked up. Good quality units. I'll take it if you're gonna junk it.

That brake line runs to one of the outputs on the master cylinder.
 

bucket

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Several years ago I bought a 72 Camaro. Had some kind of sensor under the body and something on the drive shaft that triggered it every rotation. Found out it was some kind of aftermarket cruise control apparatus. I think someone told me they came from Sears when I posted pics of it on NastyZ28. I don't remember there being anything inside the car for it though. Just speaking of odd old things.

Ha! Even found the post from 2007. :p


I worked at a junkyard for a bit in '02/'03 or so. I remember taking apart several cars with aftermarket cruise control like that. I don't remember what the switchgear looked like on any of them. I just remember the janky sensor setups.
 

legopnuematic

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@brooksman9 @bucket

My 76 had an aftermarket cruise setup like that. Magnet glued to the driveshaft with proximity sensor self tappered to the floor. Magnet flew off in the first week of owning the truck.

I pulled everything out of the truck not long after, kept it though in a shoe box. The “control” switch was mounted to the turn signal stalk.
 

bucket

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@brooksman9 @bucket

My 76 had an aftermarket cruise setup like that. Magnet glued to the driveshaft with proximity sensor self tappered to the floor. Magnet flew off in the first week of owning the truck.

I pulled everything out of the truck not long after, kept it though in a shoe box. The “control” switch was mounted to the turn signal stalk.

The ones I remember had what was basically a hose clamp holding the magnet to the drive shaft.
 

75gmck25

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I installed a couple aftermarket cruise controls, and they both had two magnets you epoxied to the driveshaft. Then you mounted a sensor on the body and it stuck out near the driveshaft (1/4”?). Magnets spinning around near the sensor were used to measure road speed.

However, the device shown in the first post is a trailer brake controller.
 

59840Surfer

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The problem with the hydraulic brake controllers is that they "stole" some fluid from the discharge of the master cylinder, and whatever position they were installed in (front or rear) suffered a bit for pressure and application volume.

Initially, they were designed for the old single-system brakes where all four wheels had fluid from the same single pressure system.

This was typically before dual brake systems, and if I found these on a dual-system, I used to fail them on the inspection.
 

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The problem with the hydraulic brake controllers is that they "stole" some fluid from the discharge of the master cylinder, and whatever position they were installed in (front or rear) suffered a bit for pressure and application volume.

Initially, they were designed for the old single-system brakes where all four wheels had fluid from the same single pressure system.

This was typically before dual brake systems, and if I found these on a dual-system, I used to fail them on the inspection.
Sounds like wives tales. If that little extra displacement causes brake issues.. Once bled and equalized, there should be barely any extra displacement of fluid.

Then normal brake wear should cause no brakes, going off that theory. Normal brake wear is 10x the displacement of that fluid. Caliper pistons will extend pretty far. Also every inch of hardline should matter too with that theory. I'm sure there's some ridiculous distance where you wouldn't get the same pressure as "normal".
 

59840Surfer

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Sounds like wives tales. If that little extra displacement causes brake issues.. Once bled and equalized, there should be barely any extra displacement of fluid.

Then normal brake wear should cause no brakes, going off that theory. Normal brake wear is 10x the displacement of that fluid. Caliper pistons will extend pretty far. Also every inch of hardline should matter too with that theory. I'm sure there's some ridiculous distance where you wouldn't get the same pressure as "normal".
You're 100% wrong.

The small cylinder-piston in the controller takes fluid to make it travel. This is not the same as brake wear --- it's totally out of that realm --- totally.

If it takes fluid, it decreases the ultimate volume sent to whatever side of the brakes in which you've installed it --- front or rear.

I know. I was a Brake/Lamp/Smog Inspector and I had tried that same hydraulic controller on one of my dual-brake systems and it just did not work.

Believe what you want - but don't go popping off with theories that might get someone else injured or killed or kill a vehicle in the opposing lane.

Any time you take fluid to move that device - it takes from that system and cuts the flow to (usually the rear) brakes.

Stop being ignorant --- you cannot use this brake controller on anything but a single-system master cylinder - and even then it can feel different because of the change in fluid to the brakes.

These were originally designed to be used on the (much) older single-piston master cylinder systems in cars and trucks that were crushed and returned as Toyotas long before you were born.
 

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