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How to Install a Fold-Away Coupler Hinge Kit on a Trailer with Surge Brakes  


Can I get part BH 3MFS-20 with a 90 degree male on one end


Expert Reply:

In order to install a Fulton Fold-Away Coupler Hinge Kit like part # FHDPB230101 on a trailer with surge brakes you are going to want to use a flexible brake line that runs from the actuator to the t-fitting just before it splits to each braking assembly. This hose can been seen as letter A in the attached photo. The hose can actually be ran through the frame rail you will just need to make sure you have enough slack so it does not put too much tension on the line when the tongue is in the folded position. Therefore, the flexible brake line you choose needs to be longer than the distance from the actuator to the t-fitting.

In regards to the type of fittings, they will need to match the actuator which is usually a female 3/8"-24 and the t-fitting which is also usually a female 3/8"-24. For a flexible brake line that matches these fittings and is 18' long I recommend part # BH-3MFS-18. For the t-fitting you could then use part # BH-T-3FIF.

Unfortunately, we do not have a video that shows this installed on a trailer with a fold away hinge kit.

expert reply by:
Conner L
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Dana V.


I have a 2X3 inch bolt on kit from you. Noticed some 2020 kits that have broken out there....My tube is 2.010 X 3.010 BUT the Fulton bolt on casting is 2.100X3.100 inch inside diameter. THAT is a 0.090 inch gap ALL AROUND. Have a hard time thinking good to torque on a casting with that kind of gap!!!! Could you have lost the bubble on quality and they are being made too big! Is this dangerous if torque micro cracks casting and stress corrosion breaks later..... Is my new unit defective?

Etrailer Expert

Jon G.


I'm not seeing any of our reviews coming back talking about it breaking (and it would be good to make sure that anyone stating this installed this correctly and isn't overloading it). I would imagine that there would need to be the slightest bit of a gap so that the hinge can actually fit around the coupler itself, and from what you found there is less than 1/10 of an inch difference between the hinge kit and your trailer coupler. This still comes with a 5-year warranty which I think speaks for the quality in and of itself. If you're concerned with that 1/10 of an inch difference then I'd try reaching out to Fulton to get their take on your findings.



Can I get part BH 3MFS-20 with a 90 degree male on one end

Conner L.


The Kodiak Hydraulic Brake Hose part # BH-3MFS-20 is not offered with a 90 degree male 3/8"-24 flare fitting. However, you can join the Kodiak Hydraulic Brake Hose part # BH-3MFS90FF-1-5 to the above hose and obtain the 90 degree male 3/8"-24 flare fitting that you need.

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