A Disco doesn't call for that sort of air pressure, they are not delivery trucks.

 

46 psi is fully loaded with passengers and a bunch of crap in the back. I think I have around 40, maybe a little less.

 

My D2 came with Geolander H/T-S from the PO.
Got lots of milage left on them and seem to be a pretty good all around tire,
except are noisier than I like.
They are rated to 51 PSI.
My door jamb says 28 PSI front (cold) & 46 PSI rear (cold).
I run the fronts at 33 PSI, don't know if the factory brush bar adds that
much weight & the rears at 38 PSI. Never really carry any passengers or cargo.