CobraDave
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Here is a short write up on my trailer brakes and how brake calipers are rebuilt. I thought on one of my wheels the brakes were dragging so I took it apart and realized the pad contact was normal. Then I got curious of how calipers are assembled and did a quick rebuild for my own knowledge. The parts are really cheap and if you have the time, don’t let a trailer shop tell you you need a new caliper. 9 times out of ten you just have to clean it up and replace a seal if it’s stuck. Disclaimer, I hardly consider myself a mechanic and am sure there is a better way to do things.
First, I’m dealing with a two year old Extreme Trailer with disc brakes on the front axle. The calipers are UFP dB-35 made
by Dexter. Take the wheel off and use a jack stand and wheel chocks. This is what it looks like.
View attachment 769809 View attachment 769811
Next, there are two bolts holding the caliper on. They have red loctite so prepare for a fight. It takes a 14mm socket.
Once off I removed the brake line at the hydraulic fitting using a 5/8. Be prepared for some fluid to come out but it’s minimal.
From there the caliper is off and taken to the bench. I noticed some rust on the rotor and lugs. I’ll clean that up later. Remove the brake pads and anti rattle clip.
Pads looked new but very dry.
From here you can separate the two caliper pieces by sliding them out. The guide pins were a little stuck which could effect braking for sure. Also there was some slight rust on the piston. I sprayed a little brake cleaner which freed them up.
Then you can remove the guide pin caps and the rubber guide pin sleeves. They just pull out. Remember how they go back.
Now it’s time to get the piston out. They’re two seals in the caliper. One is the dust seal which you see on top. Another is the inner seal. The top dust seal pulls right off. Remember the hole where you removed
The brake line? Use some compressed air to blow in the hole which will force the piston out. You don’t need much so be careful. I’ve seen videos online of using a bike pump. The piston could fly out so use something to take the impact. I used my kid’s sandal. Lol
Now inside is a squared seal which I removed gently with a small screwdriver.
So you’re about done with disassembly. You can take the guide pins off but they are one there pretty good and mine were pretty clean. They take an Allen wrench. Might be best to remove them while it’s still on the trailer.
Also you can replace the metal slides that the pads glide on. I’m just going to clean
them up. All metal goes into some gasoline for a bit then I’m going to wire brush them.
To be continued.
Sent from my iPhone using Tapatalk
First, I’m dealing with a two year old Extreme Trailer with disc brakes on the front axle. The calipers are UFP dB-35 made
by Dexter. Take the wheel off and use a jack stand and wheel chocks. This is what it looks like.
View attachment 769809 View attachment 769811
Next, there are two bolts holding the caliper on. They have red loctite so prepare for a fight. It takes a 14mm socket.
Once off I removed the brake line at the hydraulic fitting using a 5/8. Be prepared for some fluid to come out but it’s minimal.
From there the caliper is off and taken to the bench. I noticed some rust on the rotor and lugs. I’ll clean that up later. Remove the brake pads and anti rattle clip.
Pads looked new but very dry.
From here you can separate the two caliper pieces by sliding them out. The guide pins were a little stuck which could effect braking for sure. Also there was some slight rust on the piston. I sprayed a little brake cleaner which freed them up.
Then you can remove the guide pin caps and the rubber guide pin sleeves. They just pull out. Remember how they go back.
Now it’s time to get the piston out. They’re two seals in the caliper. One is the dust seal which you see on top. Another is the inner seal. The top dust seal pulls right off. Remember the hole where you removed
The brake line? Use some compressed air to blow in the hole which will force the piston out. You don’t need much so be careful. I’ve seen videos online of using a bike pump. The piston could fly out so use something to take the impact. I used my kid’s sandal. Lol
Now inside is a squared seal which I removed gently with a small screwdriver.
So you’re about done with disassembly. You can take the guide pins off but they are one there pretty good and mine were pretty clean. They take an Allen wrench. Might be best to remove them while it’s still on the trailer.
Also you can replace the metal slides that the pads glide on. I’m just going to clean
them up. All metal goes into some gasoline for a bit then I’m going to wire brush them.
To be continued.
Sent from my iPhone using Tapatalk