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I bought another Steering box so I can check the nut out (expensive solution) . It looks like a M12 but it may not be metric as I bought an M12 and it doesn't quite fit. So here is the one off the new box. The question still stands what are these nuts what is the red stuff - some kind of silicon seal? and where do I get them from?

Yes I think so, the one that screws on to threaded rod. See picture

PS its a Defender 300tdi

Hi, A question for the brain trust, I have power steering fluid coming out of the top nut of the power steering box - what does this mean? I took the nut off and there is no seal but looks like the nut has had locktite or similar around it. Can I just put a new nut on with some fresh locktite or does this mean seals have gone elsewhere in the box? Thanks for the help