Lack of steering self centering

A friend drove my 300tdi 90 and commented on the lack of caster/self centering. There some self centering but I usually have to help it back to the ctr.

I then drove his and indeed it's better.

Mine has not be raised so what do I need to check pease

have you got large tyres?if you jack front up and turn wheels(by hand on the tyres) you see it its free or binding in swivels or pas box (over adjusting pas box can cause this)_

The tyres are 265/75x15 BFG Mud Terrain - is this big?

Mine wouldn't self centre when I brought it, I adjusted the grub screw on the steering box 1/4 turn anti clockwise and now it self centres.

Cheers for that, will have a look

Was your steering stiff with the wheels off the ground

I wouldn't just go loosening the grub screw yet, it is for ajdusting steering wheel play, and would if over adjusted cause binding which may reduce the ability for the system to self centre.

It is like installing a sprinkler over faulty electrical equipment that keeps bursting into flames, sort the issue first. As James said above check the swivels first, before you actually build too much play into your steering system

Definitely don't tighten it up or you'll lose self centering completely, and it'll be too late. I speak from experience