Brakes working correctly?

[Dbraw]

Just installed a brake box on the truck and am checking the brakes on our 1971 Safari. When I activate the the brake manual control, the two rear brakes on the trailer seem to be the only ones to engage. When I use the brake pedal on the truck, the truck and trailer stops like it should. Is the correct? Also, how do I determine if all the brakes on the trailer are engaging?
Dan

[kaffe_1477]

Jack up the triler...so that all of the wheels are off the ground. have someone mash the break peddle then try to turn the wheels by hand. You should not be able to.

[overlander63]

Originally Posted by kaffe_1477

Jack up the triler...so that all of the wheels are off the ground. have someone mash the break peddle then try to turn the wheels by hand. You should not be able to.

The brakes on the trailer should be electric drum, and any brake pedal application of the truck's brakes while at rest will have no effect.. You can check operation of the brakes by jacking up the trailer, one side at a time, and apply the trailer brake controller, and see if you can spin both tires. If both can't be moved, the brakes are working, if one doesn't work, you probably have a bda magnet or a bad wire or connector going to the magnet. You can check magnets without jacking, by applying the trailer brakes, and holding a cheap compass near the wheels. If the compass points at the wheel, the magnet is good.

[Excella CM]

Yes, that is correct. The controller manual brake lever supplies power to the trailer brakes via an electrical signal. The truck brakes are not activated by the controller. If only one brake is working on the trailer, it will cause the truck to veer in the opposite direction when the hand lever is applied. The trailer brakes need to be in proper adjustment to stop evenly as well. From your description it sounds as if the brakes are OK.

[kaffe_1477]

Originally Posted by overlander63

The brakes on the trailer should be electric drum, and any brake pedal application of the truck's brakes while at rest will have no effect.. You can check operation of the brakes by jacking up the trailer, one side at a time, and apply the trailer brake controller, and see if you can spin both tires. If both can't be moved, the brakes are working, if one doesn't work, you probably have a bda magnet or a bad wire or connector going to the magnet. You can check magnets without jacking, by applying the trailer brakes, and holding a cheap compass near the wheels. If the compass points at the wheel, the magnet is good.

Sorry about that...I guess I am a little confused about how it all works. Doesn't the brake controller send the voltage to the drums when the break peddle is pressed and depending on the preset level you can adjust the amount of voltage that regulates the braking force of the trailer?

[scottanlily]

Yes it does do just that . you apply your brakes and the controller sends the voltage signal to the trailers brakes ,as does the manual lever as well .the manual lever at full movement applies full voltage to the trailer brakes.If I
step on the brakes in my TV at the stop light ,the trailer brakes do indeed have voltage applied to them ,as you can read on the prodigy display .If im pulling into a gas station at almost creep speed ,the trailer brakes drag on the Tv and the prodigy shows voltage is applied also ,it is a low voltage .
when I tested my brake magnets for the hum ,I just applied the travelalls
brake pedal ,Ive never used the manual lever .not once so far ,haven't needed to .so I don't no if the controllers you all are using are working right
or what ,im not sure .

Scott

[doorgunner]

Hi Scott Still dealin on the duramax wreck!

[scottanlily]

hello Tim ,how are you doing ? Well did you get the wreck or what ? I like the sound of the project so far ,I think itll turn the Sub into a torque monster.
A customer of mine has a 96 with the 6.5 turbo in it factory with 4 wheel drive and he just loves it .Its a rare one as most Suburbans came with the
big block or the 5.7 .

Scott

[krwrite]

Another method of testing if brakes are actuating is to get a cheap compass. Have someone engage the brakes and hold the compass near the drum. If it is getting power, the drum magnet will make the compass needle swing toward it. That's a quick way to check without getting out the ampmeter or jacking it up.....Try this first and then go to other methods if needed.
Ken... 76 sovereign. Alabaster, Alabama. krwrite@yahoo.com