Leaking NH tc45d

Is the fitting split, or is it loose? Do not use any sort of appendage or bit of skin to check where the leak is, or how bad it is. Use a piece of cardboard or the like. The hydraulic oil under pressure may not be seen, and it can penetrate the skin.... way bad thing to happen.
Anyways, it's a pretty standard fitting. A couple of wrenches and you should be able to tighten it snugly if that's your problem.

I've got the same loader on a TC40DA and it's really easy to adjust that fitting. Just tighten it. I put thread sealer on them just because, but no leaks on mine.
I've had mine for several years now and can attest you should take grease and slather it over all those fittings on the loader cause they WILL start to rust and of course you know what that means. I have had one of the lift cylinder's rebuilt too, it's just part of it. But I just can't do without my NH.