Shogun Sport 2001 - Mitsubishi Shogun Sport brake load valve

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Mon 7 Sep 2020 18:20
Shogun Sport 2001 - Mitsubishi Shogun Sport brake load valve - lohr500

Hi all,

Does anyone know how the rear brake load proportioning valve works on the above vehicle?

I understand the basics of a load valve, but this one has two inlet pipes and one outlet. The single outlet feeds both rear brakes via a flexi and T piece on the rear axle.

As far as I can see from various diagrams one of the inlets is the rear brake line from the ABS unit and the second inlet is a feed from the front brake circuit. There is a single bleed nipple on the load valve.

I have a split pipe on the outlet side of the valve which is causing the rear brakes to fail and the master cylinder fluid reservoir drops to the MIN level. But the front brakes are still working OK and the fluid doesn't go any lower. So the dual circuit part of the system is working.

I think that the feed from the front brakes which goes into the brake proportioning valve must only work on some internal piston/regulator and is not directly linked to the rear brake line. Otherwise the remaining fluid in the master cylinder reservoir and pressure to the front brake circuits would also be lost. I'm also thinking that the bleed nipple on the valve must be to bleed this same feed from the front brakes.

Would this make sense?

Any insight would be much appreciated.

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Tue 8 Sep 2020 11:22
Shogun Sport 2001 - Mitsubishi Shogun Sport brake load valve - focussed

The load proportioning valve is there to limit the brake system pressure to the rear brakes when the load on the rear axle is light. So common sense says if it limits the pressure there has to be a means of dumping the excess pressure and returning it to the abs unit low pressure side. This also has the effect of moving brake fluid around the load proportioning valve and abs unit to keep them flushed, active and clean.

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Wed 9 Sep 2020 16:03
Shogun Sport 2001 - Mitsubishi Shogun Sport brake load valve - lohr500

Its possible focussed, but the earlier versions had no return line. The pressure was just regulated by a simple one in/one out valve. According to the brake diagram, the pipe from the front brakes comes from the high pressure side of the front circuit on the feed to the front right caliper. So I can only assume the three way valve is taking into account the pressure in the front circuit. Perhaps it is so if the front circuit fails, maximum pressure is applied to the rear, regardless of load.

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Sat 12 Sep 2020 23:09
Shogun Sport 2001 - Mitsubishi Shogun Sport brake load valve - focussed

I've got an L200 which is related to a Shogun. I don't think it quite works like that. Some members of the owner's club have had to replace the load proportioning valve - if it isn't properly adjusted it locks the back wheels up under normal braking - so maximum pressure to the rear is not what you want.

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