DUAL AXLE TRAILERS

[THE CUSCUS]

For those of you with dual axle trailers, do BOTH axles have brakes on them? If not, which axle has the brakes (front or rear)? I am planning to add a second axle, and remember reading here that one location was better than the other for the braking axle, but I don't remember which. Thanks for your help.

[MadMacX]

It's always the front axle. If you can afford it, add brakes to both axles.

Pat

[Doug91mac26s]

I rebuilt an old Pacific trailer. It only has brakes on one axle, the rear one, that's the way it came from the factory. I converted the old drum brakes to stainless steel disc brakes.

[DaveB]

I have a 2 yr old Aluminum that I put Surge brakes on front Axel, they recomended rear Axel but the hydrolic line wouldn't reach. They are Stainless steel disks.
Law requires brakes on each axel but the boat stops very well with one set (the stock Mac. trailer single axle only have one set).
The back up selinoid started leaking after a year and bought replacement and sprayed with plastic as original had steel it and rusted. I only launch in Salt water.
Putting 4 disk brakes is way over kill for a Mac. and more maintanance.
I trailered the boat 450 miles with new Trailer round trip to the keys twice with no brakes when it was new and had to leave a lot of space when brakeing. I know brake normal but still leave a safe distance in Auto's in front.
Dave

For those of you with dual axle trailers, do BOTH axles have brakes on them? If not, which axle has the brakes (front or rear)? I am planning to add a second axle, and remember reading here that one location was better than the other for the braking axle, but I don't remember which. Thanks for your help.

[Doug91mac26s]

I agree with Dave, considering our Mac's are so light, brakes on one axle is fine. My original Mac trailer had no brakes at all. The trailer I use now with brakes on one axle stops very nicely. If I was hauling a much heavier boat, brakes on both axles would be warranted. But having said that, if you've got money to burn, brakes on all the wheels is good!

[THE CUSCUS]

Thanks everyone for your replies. I do agree, brakes on both axles would be best (overkill for 3000lbs though), but the initial cost and additional maintenance are big negatives. My boat will be kept at a slip, so I only need to go about 40 miles, twice a year. It looks like we're split 50-50 on which axle (front or rear) is best to have the brakes on. Anyone witha "scientific" reason for brake placement?

[MadMacX]

Thanks everyone for your replies. I do agree, brakes on both axles would be best (overkill for 3000lbs though), but the initial cost and additional maintenance are big negatives. My boat will be kept at a slip, so I only need to go about 40 miles, twice a year. It looks like we're split 50-50 on which axle (front or rear) is best to have the brakes on. Anyone witha "scientific" reason for brake placement?

There are two schools of thought that I'm aware of......1) Rear axle brakes because when stopping the axles rotate and by doing so, it adds more weight to the rear axle. 2) Front axle brakes because you are less likely to back the trailer into the water to the point of submerging the front axle and, if your trailer is loaded correctly there should be more weight on the front axle than the rear axle, so there is more bite on the front axle when stopping.

I have always had front axle brakes on my trailers, but others claim just the opposite. Champion Trailers recommends rear brakes on their site;
"When only one brake axle is being installed on a tandem axle trailer, the brakes should be on the rear axle for maximum system performance. Rotational torque applied to axles during braking shifts the equalizer and applies more weight to rear axle. If brakes are installed on the front axle, the wheel may skid during braking. Brakes on rear axle are more effective as the equalizers shifts and the rear tires dig in to the pavement".

I guess it's six of one and half a dozen of the other.

Pat

[flynfol]

I had electric brakes on my 22' powerboat. (We towed long distances) I'm thinking it weighed about 4000+ lbs. Rear brakes only on tandem axles. Worked great. We only operated in fresh water. Wiring was all PROPERLY soldered and sealed. The brake parts are the same, only difference is how they are actuated. Dragging magnets on cams versus hydraulic pistons. They ALL need maintenance at least you won't have to bleed them.(which should be done regularly to prevent corrosion....brake fluid is hygroscopic) They are only submerged for a couple minutes and probably get more exposure from rain while driving. How many people worry about the wiring going to their submerged wellpumps..... which is continously for years. I like the control you have from inside and the ability to TEST/ADJUST them.

Drawbacks are needing a controller installed in the tow vehicle.

It is an option.

John

[Doug91mac26s]

As I mentioned previously, my Pacific trailer rated for 6500lbs., came from the factory with drum brakes on the rear axle only. When I was going through the rebuild process and was converting to SS disc brakes, I asked the factory rep which axle is best, they told me the rear axle. I couldn't remember the reason given, but when I read the quote, provided by MadMacx, from Champion Trailers, who also recommends the rear axle, I realize that is what Pacific told me as well.

So I'd recommend if you're going with brakes on one axle only, go with the rear, as recommended by both Champion and Pacific Trailers. If you're still unsure, why don't you pick up the phone and call another trailer manufacturer and see what they tell you.

[waternwaves]

The only reason to have the breaks on the rear of two axles is to have a smoother ride.

This is a common analysis problem for specialized over the road trailers.
If you want to stop the trailer quickly, front brakes will stop the trailer quicker. The problem is that additional force presses down on the trailer hitch and decreases the effectiveness of the tow vehicles front brakes. (and most of your braking is done with your front brakes.)

For a smoother ride and better control put the brakes on the rear axle.

But if you have a load that is balanced with a specialized tow vehicle, equalizers, and travels at relatively lower speeds, brakes on the front axle stop the towed vehicle faster.

When you are carrying nuclear shipping casks, decommisioned Submarine reactors and the like, you analyze the effects of brake location very very carfully.

[DaveB]

I might add that my twin axel is connected between the two axels by a piviot arm that the two leef springs attach to. In bracking this would cause the front brakes to have much for traction from tires than rear.
For example: if you aply the brakes the pivit on the arm will lower on your front axel .
Hope this explains it.
On the other hand if backing down a steep ramp the rear axel has more grip on tires.
I would think also haveing front brakes one still has ramp left.
I just convinced myself that front brakes are better, works for me.
Dave

Thanks everyone for your replies. I do agree, brakes on both axles would be best (overkill for 3000lbs though), but the initial cost and additional maintenance are big negatives. My boat will be kept at a slip, so I only need to go about 40 miles, twice a year. It looks like we're split 50-50 on which axle (front or rear) is best to have the brakes on. Anyone witha "scientific" reason for brake placement?

There are two schools of thought that I'm aware of......1) Rear axle brakes because when stopping the axles rotate and by doing so, it adds more weight to the rear axle. 2) Front axle brakes because you are less likely to back the trailer into the water to the point of submerging the front axle and, if your trailer is loaded correctly there should be more weight on the front axle than the rear axle, so there is more bite on the front axle when stopping.

I have always had front axle brakes on my trailers, but others claim just the opposite. Champion Trailers recommends rear brakes on their site;
"When only one brake axle is being installed on a tandem axle trailer, the brakes should be on the rear axle for maximum system performance. Rotational torque applied to axles during braking shifts the equalizer and applies more weight to rear axle. If brakes are installed on the front axle, the wheel may skid during braking. Brakes on rear axle are more effective as the equalizers shifts and the rear tires dig in to the pavement".

I guess it's six of one and half a dozen of the other.

Pat

[flynfol]

I think that pivot arm is called an equalizer(axle). My boat had them too. My electric brakes did not work in reverse(they rely on forward rotation), and I don't thing a hyd surge is designed to work in reverse either. I see what waterwaves is saying....makes sense about putting the added weight on the tongue (center of mass..seesaw priciple)if you use the front axle. I suppose you could install a weight distributing hitch with a front axle brake.........I kinda like the retro rocket and dragchute idea myself

[DaveB]

Thats right. Surge brakes have a silonoid that prevents the brakes locking up in reverse. Good point when useing these brakes backing down the ramp.
Dave

I think that pivot arm is called an equalizer(axle). My boat had them too. My electric brakes did not work in reverse(they rely on forward rotation), and I don't thing a hyd surge is designed to work in reverse either. I see what waterwaves is saying....makes sense about putting the added weight on the tongue (center of mass..seesaw priciple)if you use the front axle. I suppose you could install a weight distributing hitch with a front axle brake.........I kinda like the retro rocket and dragchute idea myself

[Doug91mac26s]

The backup solonoid on a surge brake system is to prevent the brakes from engaging while backing up a hill, not down a ramp. Going down, the trailer will pull the acuator away from the tow vehicle, which does not apply the brakes. While backing up a hill the trailer will push toward the tow vehicle pressing on the actuator, activating the brakes, which is why the lockout solonoid is required.

[waternwaves]

having not seen your tow rig....

Even if I had a loaded pickup, with equalizers, and a boat and trailer that weighed half of the truck and doing 100 kph(62mph).......I would still put the brakes on the rear.

Less than half the weight of the truck I would not have a problem with the brakes on the front.

for a passenger tow vehicle, I would only put the brakes on the rear because of the closeness of fore aft weight distribution in passenger vehicles and the light weight of the frames, and the light passenger vehicle suspensions.

JMHO YMMV