Tractors4u
Elite Member
- Joined
- Mar 10, 2002
- Messages
- 2,540
- Location
- Athens Alabama
- Tractor
- Deere 4310, Kubota L355, John Deere SST18 Spin Steer, 2006 Polaris Ranger
Those plastic plugs are to protect the threads on the hole they are in. I don't think they are hydraulic ports. If they were the plugs would be made of metal and threaded. Just guessing, but I would say that the holes are there to bolt on some optional piece of equipment. My Japanese dozer has thos holes all over it and the holes are plugged with cork plugs.