Brake voltage

MrDudeSir

Member
Hi, on a 3500# axle, at what voltage, approximately, should the wheel be impossible to turn by hand, with the trailer jacked up? I had controller set to 2.0v and can't turn left side, but have to set up around 4+ before the right side is hard to turn. Trying to figure out if I should focus on adjusting the left or right side.

When voltage is zero, I can spin the left about 3 times and right 6 times, with moderate effort.

These are new hubs, bearings and self adjusting (generic) brakes but appear to be well made.

Any advice appreciated. Thanks!
 
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rhodies1

Well-known member
Sounds like the left maybe a little too tight. I would slack this side off a little to see if you can get both sides equal .
With the left grabbing quicker it will pull to the left during stopping.
 

hoefler

Well-known member
Since everything is new, consistant results cannot be expected until the brake shoes, drums, magnets, etc.. are burnished in. This will take anywhere from 500 to 1500 miles depnding on driving conditions that require braking. Will also require adjusting several times to get even braking. The shoes are not making full contact with the drums when new, any residual oils from handling when assembling from your hands will have to be burned off, magnets will also have to have wear in time as well to make full contact with the drum face, if the magnets are used, they will have different wear patterns and are different thicknesses from surface to coil from each other. Which will require wear in time as well. If the wiring to the drums are feed throught the axle tubes, the wires will chaffe, will have an electrical bleed to ground or even short to ground. This will be worse if moisture is trapped in the tube. Your rig is most likely wired just like every other rig out there, the power goes to the left front or the right front first, then spliced to go to the second axle and the other side of the front axle, then splicerd at the second axle, 3rd brake assembly, and then to the last assembly. Every connection creates resistance, the first assembly in line will get the most voltage/amperage and will always activate first and the strongest. The 4th assembly will always have a delay, altho slight, and will have the least power to operate.
 

MrDudeSir

Member
Thanks. I bench tested brakes individually when new for ohms and amperage draw at 12v and both were same, and same when installed (total combined). I soldered the connections to reduce resistance and to weather better.

I think the right was a bit loose so I tightened up a bit. Took off hub, and I sanded shoes a bit and cleaned while in there.

Now, they are about 2.5v vs 3.5v where they lock up enough that I can't turn wheel.

I might tear into the left and loosen a couple of clicks and clean up and call it good while I have it at home.

Actually drives pretty well and setting at 5.5 max seems about right.

Our TV has stability control and manual says it kicks in while towing so I haven't noticed it pulling hard during breaking. But I'd rather get it as balanced as I can.
 

MrDudeSir

Member
Thanks. The manual says you can loosen the shoes with the hubs on, but with the self adjusters, the star wheel is 'ratcheted' so I didn't see how that would work. Easy enough to take off so I did that. I think I have them balanced out now but will check again after my next trip.
 

rhodies1

Well-known member
You use 2 screwdrivers. One to left the lock away from the star wheel and the second to adjust the star wheel. Easy job
 
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