Implement lift arm pins

I am having issue with the pins where the 3 pth implement pins run through the balls on the lift arms. This is a JD 5525 with cat 1 and 2 balls in the lift arms. I normally run my stabilizers not jammed tight but snug. This has happened with two implements which are both cat 2 and have run them both on a Kubota M6800 which has Cat 2 balls in the lift arms with same type of stabilizers the sliding metal ones.

 

First happened with a boom mower with a flail head on it, the pin coming out the left lift arm allowing the cutter head to drop swinging the cutter frame into the left rear tire. Not the cutting head but the frame. I was using the regular hitch pin like used with a trailer pin but I always push them in all the way and not in the little first place some people will leave them. I replaced the pin and ran cutter for maybe another hour ok. But the next time I used it was using same type of pins and after cutting with it say 15 minutes checked and they were coming out. One had just dropped when I checked it. I went to the lynch pins with the spring circle that you flip open to install or remove and did not have another issue with the boom mower. Now the boom mower was being used to cut high limbs, under trees and all kind of angles. So the connections were being pushed.

 

Now have used subsoiler on the same tractor with the lynch pins and it was in really hard dirt with a lot of vibration due to hardpan. It was used in this for say 10 hours with last few hours nephew running it. When it got back to me the lynch pins were missing. I had him to cut around tree line at my house and he hit a root that popped shear bolt and it was very loud. I would not be suprised if it shook the subsoiler as it also twisted the shank the bolt sheared on. I can believe it is possible one of the lynch pins sheared with the subsoiler jumping the way it hit the stump but hard to believe it could have sheared both. 

 

The tractor in both cases was running very low ground speed.  Have come to the thought need to get "LOCKS" with shanks that would be long enough to clear to be fully certain vibration and other movement was not loosing the pins.  There has to be something I am missing. Maybe in the times I have used a 3 pth implement not aware ever dropped an implement or loss more than one pin or two and that on a selection of tractors. Have wondered it I need to place a flat washer between pin and the lift arm.  Thanks for your help

 

 

 

Implement lift arm pins