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You might consider having the brake shoes modified to match the brake drum... There are plans that do this... They need drum and brake shoes... They are not as common as they once where... Iv hear there is a noticable difference.

yes. find an old auto repair shop that still rearches brake shoes. most stopped this practice because of asbestos in the linings. we had one where i worked, but would only use it if we knew the lining was asbestos free
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rz

When you say blocked the proportioning valve what do you mean. That valve needs to be completely open.?
Linda S?

I used to race SCCA and we tried to use DOT 5 silicone brake fluid as you mentioned and it is great for ultra hi temps and will not absorb any water which could cause corrosion in your brake system,? but the DOT 5 fluid is ever so slightly "compressable" compared to non silicone brake fluids.? This means it will INCREASE the brake pedal spongeiness just a little bit ( somewhat like a few air bubbles in the fluid)? ?so if your brakes are marginal to begin with the silicone fluid will make them a little worse.? ?

I've seen some bypass and removal video's but they either wouldn't be enough or over complicated. Most do just what you have already done.?
I keep wondering if the valve itself couldn't just be gutted. Transferring brake pressure with no obstructions. If someone finds out how to do it I'd be interested.?
What brand are your new brake shoes. I've had problems with Centric and my mechanic son in law had some too. In my case the shoes for my dually Nissan didn't fit at all.
The ones he bought for a 4runner were so out of round they couldn't be arched enough to fit the drum properly. All not good.?
Linda S

OK, some basic brake physics (which some of you may already know but it's good to review).

The proportioning valve is there for two reasons: The first is the fluid pressure and volume demands for disc brakes and drum brakes are very different.
The second is that the relative requirement for front and rear brakes changes with how much weight load is added towards the rear of the vehicle.

The actuator arm you removed from the valve is supposed to sense weight load (more weight = more spring compression = change in relative geometry
of the position of the actuator arm = more brake pressure to rear brakes).

If, with the arm fully removed, you are still getting insufficient pressure to the rear brakes, it may be that the valve has failed somehow internally. It could
also imply you have a restriction in the brake hoses aft of the proportioning valve. Or, it's possible the master cylinder is not delivering full design pressure
to the rear brake circuit.

The simplest soution may be to remove the proportioining valve and install a manually adjustable one in its place.



If you do this, please adjust the valve carefully and test your brakes thoroughly in safe area. A crucial function of the proportioning valve is to deliver best possible
braking at the rear while NOT ALLOWING the rear brakes to lock up before the front ones. Being in a hard braking scenario with the rear wheels locked is a nightmare scenario.

Finally, I don't know exactly how your ToyHomes brakes are behaving, but we must have realistic expectations. The two things that vehicles with supeior brake performance have
in common are A) Low relative mass and B) sticky tires. Neither of those conditions apply to our ToyHomes.

Good luck and please let us know how your efforts turn out.

Buzz L
Phoenix, AZ
Former '86 Dolpin 500, '89 HiLux longbed, and '96 Tacoma owner

Robert keep us posted, I have had the same issues with my brakes since I have owned 18 Nissan Sunrader. Lots of front braking, weak rear. I order all my parts from Rock Auto all fit except the rear brakes shoes. My shoes were to big, I kept them for reference. I'm Still looking for a set of new shoes. My Nissan did not have a proportion valve when I bought it, don't know if it ever came with one. I'm hoping the new shoes will help.?

Re: Brake Lockup

The not-well-trained "average" driver is usually better off if the front brakes lock first. Plowing straight ahead with suboptimal braking (best braking is
right before the brakes lock up) tends to cause less chaos then locking the rear brakes and having the vehicle fishtail. Hence, vehicle manufactures
tended to build some bias towards front lockup first.

TIre retailers appy the same logic when you buy only 2 tires. They will insist upon mounting them on the rear wheels to minimize the chance
of the rear wheel hydroplaning before the front ones do.

But if you're comfortable with your vehicle control skills, then set the brake bias as you see fit.?

Buzz L.
Phoenix, AZ

P.S. I remember a very old Car & Driver article (early 1980s). I believe the title was "Beyond the Limit 101" and it discussed a driving school in Canada
where the instructors deliberately taught students to mash the brakes and induce 4-wheel lockup in emergency braking situations. Their philosophy was
threshold braking (the best possible without lockup) was difficult to master. Therefore, the most consistent way to get maximum braking in? the real world
across a variety of conditions was to mash the brakes, lock the wheels, and control the vehicle accordingly. And that's what they taught their students