Another glitch in the electric brake conversion saga. The electric brakes have a sliding magnet that rides on the inside vertical face of the drum. On a hub made for an electric brake this surface is machined flat. I haven't gotten my electric brake kit yet, but it appears that the magnet may land on the inside of the wheel bearing hub flange - no good.
The photo on the top is an electric trailer drum, the bottom photo is of a Ranger brake drum.
If I can't figure a way around this, I may have to consider a hydraulic system with surge brakes.
Tom, if when the drum is on the hub and both are the same height and nothing sticks out the magnet will still work, but nothing can stick out, and the magnet will wear crooked, but should wear for around 30,000 miles
Tom, if when the drum is on the hub and both are the same height and nothing sticks out the magnet will still work, but nothing can stick out, and the magnet will wear crooked, but should wear for around 30,000 miles
I'll know for sure when the the brakes show up, but my hunch is that the magnet falls right onto the back of the hub where the rim bolts on.
I was looking at the Dexter site and I think I could buy one close to a UHaul, with brakes for about $400. If the brackets are not welded on at the right width and the torsion arm is not 10 degrees down, you will have problems with the tire hitting the wheel well or riding too high
That will end the hassle of proprietary Uhaul parts. Take my word for it from experience - it is easier to land in an RV repair place with issues when you have a system that is standard rather than non-standard. When our hub blew in Montana a few years ago, we went to an RV repair place; they could not fix our Uhaul part, but they were heading to the Dexter place the following day. We made a hotel rez, thinking that we were going to be buying the Dexter parts to fix it and make it standard. However, a guardian angel sent us to a Uhaul dealer who used to fix Uhauls; he had a new hub.
Sometimes I think that we would have been better to choose the change to standard.
Yes, we do not know if electric brakes and VT drums would work together, because Hydraulic brake drums fit on the hub and the wheel studs stick in and would catch the magnet, as you guys used the old brake drums on the new hubs,when you had a hub go bad.
OK, I was thinking about Roger's suggestion to adapt a standard spindle to the flange where the UHaul hub mounts (first photo). It occurred to me that I could machine a sturdy adapter myself. The concept is to make an adapter like in the second picture. Insert the standardized spindle (third picture) and weld it in place. Then, just install an electric brake, drum and mount the wheel to it.
I knew I must be overlooking something. There is only about 1 1/2 inches of outboard clearance from the tire to the wheel lip, so I knew I needed to keep the tire center line in about the same place. As you can see from the sketch below, to keep the tire center line in the same position and use a standard zero offset wheel, the brakes need to be packed into about 1 1/4 inches. The standard drum is about 3 1/8" thick from the backing plate to the stud mounting face.
A second option is to keep the U Haul wheels with 1.75" offset and use a 4.75 inch bolt circle brake hub that I found at at Southwest Wheel. That leaves me outboard about 3/4". This explains why U Haul used those weird offset wheels.
I got my electric brakes yesterday. One question we had was whether the electric brake magnet would clear the hub if using a car brake drum. From the photo below, clearly the answer is no, it won't clear. Trailer hubs made for electric brakes have the wheel stud heads recessed into the casting.
The magnet can be seen at the bottom, partially blocked by the hub.
So, my plan is to press on making an adapter from the UHaul axle flange to a conventional trailer spindle. This will allow me to use conventional electric brakes, a hub with a 4.75 bolt circle and the UHaul rims, which allow enough offset to still clear the wheel lip.
First photo is the concept using the old hub and an aluminum rod to demonstrate the idea. As an aside, I think that the hub could be used with a couple of adapters sliced from 2.5" OD / 1.75" ID tubing (available on line) pressed in and welded into the bearing seats. A 1.75 " spindle would then slide in and could be butt welded in position.
The second photo is of the raw materials I picked up at a local fabricator's shop for $40. These guys are very helpful - every town seems to have a little trailer / fab shop if you can find them.
Last two photos show what others have found - the brake mounting holes are slightly off from the UHaul hub. One can clock the mounting position to use two diagonally opposite holes and drill two new ones, or drill 4 new ones. Not a big deal.
Oh yes it can be done, I just do not know why it has not been done be for, with this type of axle, if an axle goes bad, just un bolt the axle and bolt a new one on, makes sence to me
Oh yes it can be done, I just do not know why it has not been done be for, with this type of axle, if an axle goes bad, just un bolt the axle and bolt a new one on, makes sence to me
Roger, when you work on yours, please take lots of pictures of your brake system and some key dimensions of the parts. It will help others that go down this same road.
Please do post pix. We still have to get our brakes fixed. I don't entirely get this, but the hubby does, so when he is ready to work on the brakes, he can come back here.
Please do post pix. We still have to get our brakes fixed. I don't entirely get this, but the hubby does, so when he is ready to work on the brakes, he can come back here.
CindyL
I think Kevin is gonna find 25 years of rust in the brake lines. At least those should be standard fittings.
If it is rust in the passenger side line, can this be cleaned out with a long, stiff wire or some type of liquid flush? Or do I need to route a new brake line on that side? Of course, this is all just dreaming right now... we are under a winter weather watch for snow tomorrow and much colder temps.
If it is rust in the passenger side line, can this be cleaned out with a long, stiff wire or some type of liquid flush? Or do I need to route a new brake line on that side? Of course, this is all just dreaming right now... we are under a winter weather watch for snow tomorrow and much colder temps.
Kevin, I'd replace it for sure. There is high pressure in these lines and a failure could be dangerous. Also you don't want that rust to remigrate into your new parts and damage the seals.
It shouldn't be expensive, but may be a hassle to reroute.
Brake lines are very inexpensive. You may have to buy a couple different lengths and connect them with a coupler. That way you won't get involved in cutting and flaring a line. There should be one line from the coupler back to the center of the axle, a "T" at that point with a line to each wheel. Since there is suspension movement there should be a couple hoses involved too. I'd replace it all. The hoses may be the most difficult to match up. Lines don't usually plug up, they rust out, but hoses can deteriorate internally and plug. This is where a pressure bleeder is nice as you can completely flush out the whole brake system, but it can be done manually. Weather watch here too, don't think it's the same one though, our storm is coming up the coast.