I had a similar problem with my skid steer type, ISO 16028 couplers. I replaced the standard connectors on the tractor side with connect under pressure types, and that fixed that end. Then I had a problem with pressure building up in the grapple hoses and they were VERY difficult to connect, but at least doable. So a few guys on TBN gave me the idea to build these. I used my standard couplers removed from the tractor previously, screwed them into standard PVC plumbing fittings and drilled a tiny hole to ensure the pressure stayed relieved and did not build up in the grapple lines. Now I have a 100% fix. It is amazing how much pressure can build up in a closed system, in a short time period, when the temperature is under 80 degrees.
So now I just connect these couplings to the grapple whenever it is disconnected and no more problems. The center photo shows the tiny holes drilled in each



So now I just connect these couplings to the grapple whenever it is disconnected and no more problems. The center photo shows the tiny holes drilled in each


