Adding a second braking axle.

[BRICH1260]

I have a `05 Rocket tandem axle aluminum trailer with surge hydraulic disc brakes on the front axle. For safety measures I have kicked the idea around of adding a second braking axle on the rear. What is involved in doing this and how complicated a proceedure would it be to do. I am fairly mechanically inclined but do not have alot of special tools and would prefer to do this without removing the axle from the trailer or boat from the trailer. Where is a good place to purchase the parts? Also my boat`s listed dry weight is 4400lbs., am I being overly cautious?

 

[Bondo]

Re: Adding a second braking axle.

am I being overly cautious?

Ayuh,... Probably....

The aft axle won't supply the braking force of the front axle, due to weight transfer, under braking..
But, it'll no doubt add some help...

The Biggy is, Is there a brake bolt-on flange welded onto the axle,..??
If so, Ya, you can just bolt on another set, 'n plumb 'em in...
If not,...
Either the axle will need to be swapped for 1 that does, or a flange will have to be welded onto it...

 

[H20Rat]

Re: Adding a second braking axle.

The aft axle won't supply the braking force of the front axle, due to weight transfer, under braking..
But, it'll no doubt add some help...

Not doubting it, but as I think the physics of it, there isn't any weight transfer on a trailer. If anything, the rear axle is going to technically end up weighted heavier. When you hit the brakes hard, the vehicle nose dives. That will raise the hitch, which turn MIGHT transfer weight back on the boat.

Either way, with a normal tandem axle trailer, the tires should have exactly the same weight on them no matter what the conditions. The suspension is designed specifically for that.

 

[bruceb58]

Re: Adding a second braking axle.

Also my boat`s listed dry weight is 4400lbs., am I being overly cautious?

Absoltely you should add brakes to the second axle. Your towed weight including trailer and fuel would be over 5000 lbs.

 

[dlngr]

Re: Adding a second braking axle.

The weight transfer that WILL happen upon braking will make brakes on the rear axle almost useless. During hard braking,I would expect the rear axle brakes to lock up and just slide the tires on the road.

 

[Thalasso]

Re: Adding a second braking axle.

The weight transfer that WILL happen upon braking will make brakes on the rear axle almost useless. During hard braking,I would expect the rear axle brakes to lock up and just slide the tires on the road.[/QUO



Why would they be required in places, knowing that they would be almost useless as you state. There is no weight transfer on a trailer. If the rear axel would lock up first on a apllication it would be caused from an improper adjustment (shoe brakes), disc brakes on the other hand have the same pressure all through the system and therefore shouldn't lock up unless there is a caliper issue.Trailer's don't nose dive like auto's.

 

[Snowfish]

Re: Adding a second braking axle.

Many states, Minnesota is one of them, require all axles braked on trailers over 3000lbs gvwr.

The one axle braked trailers, that sneak across the boarder, are all skidders. The ones with the forward axle braked, on spring suspensions, are the worse.

Torsion axles are different story. Front or rear, one axle braked, skid equally as bad.

No physics explanation required. Just real world experience here.

Bottom line is both axles braked, whether required by law or not, is the most correct answer.

When stopping, it will feel like your not towing at all. With a properly braked trailer, I think you can probably stop better than just the tow vehicle alone.

 

[bruceb58]

Re: Adding a second braking axle.

The weight transfer that WILL happen upon braking will make brakes on the rear axle almost useless. During hard braking,I would expect the rear axle brakes to lock up and just slide the tires on the road.

With my electric/hydraulic system with Kodiac brakes, I can't lock them up manually at their highest setting so not really much to worry about there.