Adding Disc Brakes to a boat trailer with no brakes
So I'm getting ready to dump my Tundra and get a smaller suv to tow my boat and while I was reading up was surprised to learn that even though the smaller suv's say they can tow 3500 lbs you have to read the fine print and see that whatever you are towing that is near that limit has to have a brake system in it.
This is probably a good thing as a year ago I got cut off by a big rig and had to brake hard on the tundra, by some miracle I didn't jacknife the whole thing and lose Gigas in the process. I started reading up on brake systems and the way to go is disc brakes with a surge system and not a electronic brake system since we are in california.
Adding disc brakes to most trailers is super simple IF the axles have a plate welded in. From what I read, most of the axles that are rated for under 2k lbs don't have a plate, the ones over that do, the plate is normally square with four holes in it to bolt a brake system on it. Sure as shidt, when I looked under Gigas there was no mounting plate (brake flange) on the axle.
My axles looked pretty bad anyways, the last time I changed out the leaf springs I noticed that the axle was heavily pitted so I ordered a whole kit from sturdybuilttrailerparts.com. Mainly because they offered free shipping and because I had talked to them via email and the guys were really nice and helpful and their pricing was super competitive.
You have to read up on measuring axles, as it is very important you get the exact right length. I watched a bunch of videos and since I was doing it myself without help I marked off the axle and measured the hub length and remeasured several times. They had an exact replacement rated for 3500 lbs with the axle plate already installed, the new axle shipped was about 225$.
I really wanted to get a full stainless steel brake system, but I already needed a new coupler with surge brake built in and that system with the coated brakes was 560$. Adding a full stainless disc system would run another 500$ on top of that and there's no way I could afford it. More than likely in 2 years I will be redoing that brake system but I plan on doing a really good washdown with salt away every time I wash down the trailer so we'll see. Kodiac is supposed to be the best, there are other ones that I was going to get and when I read up on them on thehulltruth.com, guys said they were complete pieces of crap even though they were stainless so I went with Kodiac brakes.
If you are doing this and you have a axle with a brake flange you can skip some of the work, balancing that axle on a floor jack to get it in the right position was a bitch and a half because mine is Vbent and doesn't balance well on the jack.
You will need:
Galvanized boat trailer axle with Brake Flange
Boat Trailer Disc Brake Kit Complete with Coupler
Dot 3 brake fluid
anti seize grease
marine bearing grease
possibly a angle grinder with cutting blade or a saws all with metal blade
Cheater bar, two socket sets, box wrenches
2 floor jacks
4 jack stands
misc fasteners if you need them
lots of rubber gloves and work gloves
lots of rags
Step 1. Break the bolts on the rims on both sides, jack up the trailer one side at at time and use the jack stands to hold up said trailer. Don't even think about fugging around under a trailer with just your jack holding it, you won't get out in time if it fails. I throw the floor jack under the trailer on the side I'm working on in case a jackstand fails.
2. Remove the tires. Inspect your u bolts and mounting hardware, if it's bad you will want to order new ones and cut the old ones off. Read up on replacing the trailer bunks on this site as I did that six months ago and mine were in good shape because I antiseized everything.
3. Put one floor jack under the center of the axle and another under the leaf springs. Remove the 2 u bolts holding the spring to the axle. Then remove the center bolt in the leaf spring and carefully remove the leaf spring. Make sure there is no pressure on that spring when you are removing the bolt, hence using the floor jack to remove the pressure. Repeat on the other side of the axle.
4. Your axle is now free and the center floor jack should be holding it. Carefully remove it.
5. Read up or watch videos on adding disc brakes on BOAT trailers. This video was incredibly helpful: https://www.youtube.com/watch?v=svXWlSJWRlE
You will first have to bolt on the disc brake plate to your brake flange. The flange should be BEHIND THE WHEEL. No one told me this but I watched a bunch of videos and then called the company, they said on boats the disc brakes are normally behind the wheel to keep crap from getting into them, online it said you could do either way.
You will have to add the large bearing and seal to the back of your disc hub, then on the front side another smaller bearing and castle nut. You may or may not need to use a cotter pin, on my galvanized axle there was no hole for the cotter pin and I confirmed this with sturdybuilt. Make sure you grease the bearings as they probably are not greased.
Carefully slide on the disc onto the spindle once you put the bearings in there. Repeat on the other side.
6. Balance the axle on the floor jack and center it. You may or may not need to run a piece of non stretching rope from the front of your trailer to each end of the axle to make sure they are positioned correctly, on mine the springs have a little nub where the axle spacer goes to let you know you are in the right area. I also measured each side of the end of the axle to the spring to make sure it was centered to the trailer. Once the axle is centered, put the leaf spring back under it and add the center bolt in the leaf spring and tighten it. This keeps the leaf in place while you put your new u bolts on to hold the spring to the axle. Make sure to antiseize the u bolts and fasteners. Jack up the axle as needed to get it to the right height. You also will need to jack up the leaf spring with another jack to get it the right height and take pressure off the spring. This whole part is the hardest if you are working by yourself so just take time. You should now be done with the axle!
7. CLEAN OFF THE SURFACE OF THE ROTORS WITH BRAKE CLEANER, you probably got a lot of grease on them like I did. Screw in the brake lines onto your disc brake caliper. Add the disc brake calipers to the disc hub and fasten them in on the disc brake plate with the washers/bolts etc. Repeat on the other side.
8. Connect the T to each side of the brake lines across the axle. Then run the long line from the tongue of your trailer back to the last remaining part of the T. My kit had flexible brake lines and this was super easy. You can zip tie them or screw in holders in the frame of your trailer.
9. Remove the old coupler off your trailer, there are 2 bolts holding it on. Then replace it with the new coupler. Attach the long brake line to the actuator.
10. My kit used the Titan Model 60 Disc Brake actuator. There was zero info online about how to bleed this system so I had to look all over the damn thing until I figured how it worked. There is a bolt with a nut on it towards the front of the actuator, I've included a picture of it. What you do is open one of the bleed valves on the TOP of the brakes you installed and attach a piece of clear tubing on it. Run this tubing to a clear drinking bottle. Fill the brake reservoir about 3/4 full, then slowly push that bolt towards the back of the trailer, it moves easy at first. Keep your eye on the reservoir because you will have to fill it A LOT. Eventually it will get harder to push and you'll see fluid start to come out in that clear tube. Keep pushing until all the air is out of that clear line, there is a tiny purge inside the reservoir, you will see fluid come out of it in a stream, in fact if you push too hard it will squirt out. Ask me how I know. Tighten the bleed valve when all the air is out of the brakes and repeat on the other side.
Top off your reservoir.
11. That finishes most of your new brake/axles. You will have to get the right pin adapters for your vehicle to hook up the reverse lockout solenoid wires. This is so when you back up the trailer the surge doesn't lock up your disc brakes so you can move the trailer, otherwise you will have to make some sort of wood or metal block to keep the trailer from compressing as you back up, this activating your brakes.
The whole thing took me 6 hours from start to finish, I had never done this before and had to watch a lot of videos and I had to keep running to my garage to grab tools, it is probably 4 hours of work for a professional.
If you can turn a wrench and have time you can do this and save yourself some cash, the hardest part is getting the fasteners off and installing that damn axle.
Double check and triple check all your bolts and wiring