Adjusting Brake proportioning valve (GQ)

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3VILC
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Adjusting Brake proportioning valve (GQ)

Post by 3VILC »

Hey guys,
Does anyone know which way does what on the adjuster bolt on the GQ load sensing valve? My truck is lifted and the bolts just been wound all the way in. Should this give most or least front braking? Going to make up a spacer so I can set up the valve properly.

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Clive
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DaveM
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Re: Adjusting Brake proportioning valve (GQ)

Post by DaveM »

Dont touch the valve at all. You need to lift the bracket mount on the diff. Spring needs to sit level, and there is a measurement for spring length (can't remember this though). From memory you extend the mount inch for inch of lift.
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3VILC
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Re: Adjusting Brake proportioning valve (GQ)

Post by 3VILC »

Yup got that part, going to make an extension for the bracket, but someone has previously wound the adjuster right in, not sure which way that would set the bias but im assuming its wrong since it doesnt feel like it brakes very hard at the front. By spring length aye, cool should be easy to find what thats meant to be then
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Re: Adjusting Brake proportioning valve (GQ)

Post by DaveM »

I've always had the understanding that they are not made to be adjusted, and that doing so would do more harm than good.
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Re: Adjusting Brake proportioning valve (GQ)

Post by darinz »

It isn't a proportioning valve, it is a load sensing valve. All it does it shut off the rear brakes when there is not load on them. The best thing to do is just wire it completely shut so that the rear brakes actually work.
If it is working perfectly and modified for lift and described above then it will be good but I ALWAYS just disconect and wire shut.
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Re: Adjusting Brake proportioning valve (GQ)

Post by tweake »

if you adjust the valve or wire it up do a test run before going out on the road. do a hard stop on gravel road, fronts should lock up but rears should not.
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