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Discussion Starter · #1 · (Edited)
I was under my '92 Dakota and there is a valve of some sort, back by the rear axle area. I'm trying to figure out what this thing is and where it should be mounted, because it is just kind of hung back there. The only thing I can think of, is a proportioning valve, but what would it be doing way back there? Usually, those are mounted below the master cylinder and on the frame of the truck (on the left side, of course). Input, anyone? :confused:

Ya know, I didn't look too carefully at that valve, as to what it was hooked up to. It DID have a bleed screw on it. Is there one of those roll over protection valves on here, that is supposed to prevent the gas from spilling out of the tank? In case you can't tell, I'm grasping at straws here. Maybe I'll get a better look at this thing tomorrow, it's getting dark, but the temp finally dropped below 100 and I wanted to try and accomplish something, at least. Thanks for whatever input I can get.
 

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Discussion Starter · #3 ·
what do the lines go to? brake lines, fuel tank?

I'll have to double check, I feel so dufus that I didn't check that out better, before posting. It's just that it is over the differential, on the left side and has a bleed screw on it. I'll try to get a better look at it tomorrow and might just take a picture too. But bear in mind that the previous owner (actually, the one before him), was responsible for the oddities with this truck.

So far, I have found that:
the truck was lowered (no front springs and the rear leaf springs were stripped down to the main leaf and lowering blocks installed. In other words, the truck was actaully sitting down on the frame.

The upper shock mounts are not there!

The engine was secured with tiedown straps

The bed is just sitting on the frame (no bolts at all)

That's the main things so far. :rolleyes: I mean, for $300, I didn't expect much, after all, it DID have a clear title. :D
 

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A year late but I can offer a response.
The component you reference is the rear brake pressure modulating valve. It is the valve assembly which provides the pulsating for the rear wheel anti lock braking.
Do you still have the vehicle? I am needing some assistance with my 1992 Dakota and the rear pressure mod valve.
 

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A year late but I can offer a response.
The component you reference is the rear brake pressure modulating valve. It is the valve assembly which provides the pulsating for the rear wheel anti lock braking.

A proportioning valve is usually located at the front, between the
master cylinder and the hydraulic line taps.
The proportioning valve just modifies hydraulic pressure so that the front disk calipers get more fluid pressure around 60%, and the rear drums get about 40%.

The brake lines split off after the the proportioning valve, and go their separate
ways. A rear line goes off to the rear wheel cylinders, and two front lines, one each to the disk calipers.

I can't see how any valve located over the rear axle..unless it is just the
rear brake line splitter/Tee, right over the differential, is going to function in
the anti-lock mode.

For it to be a modulating valve, it would need to be equipped with a HCU
(Hydraulic Control Unit or in simpler words..a hydraulic pump) with it's own
wiring and controls.

I would think you would need a more complicated system..like the Kelsey-Hayes ABS RWAL system to pulse the rear line to achieve ABS.

For that you would need:

ABS sensors over each back wheel.... (or one in the differential as in the
newer Dakotas)

Some kind of HCU (hydraulic control unit with the isolation/dump valve,
as you need to keep the master cylinder pressure isolated and separate in both the
front and rear brakes, when applying the brake pressure at the master
cylinder..... to allow modulation to take at the rear wheels and not the front.

and, of course, the wiring that goes with it.
 
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