Grumbling from the front

Hello all,
New to Defenders (1997 Defender 90 Tdi)New Toy but had a Disco 1 for 3 years.
Anyway, When turning right grumbles from left hand side front wheelarch area, OK in a straight line and OK going left.
Diagnostics, is it a wheel bearing? No Clunks or clicks just grumble.
If so, do I need the dial guage (as hand book ) to measure the drive shaft free play. or can I just replace the bearing set.
Also anyone know what size the adjusting nut and lock nut are as its says torque them up, bit difficult with the box spanner I have
Any help and advice appreciated
TH

Wheel bearing seems likely to me - does it rumble with the wheel jacked or even off? Cheap and quick starting place too.....

52mm nut I think - with a box spanner I've seen a socket T bar fitted facing outwards like..... then use torque wrench and suitable socket on that?

Mine has the single nut at mega lb/ft so just do it up as tight as a tight thing........ A

Doesnt the big nut get tightened right up then loosened back a turn? Its held secure by a locking washer anyway, from what i remember the last time i had it off

hi guys eventually traced to a rotted rubber on the bottom end of the shock absorber.
Replaced and fault cured