Outer Limits 4x4 Board

Hi all, I bought a 1995 Toyota Surf SSX-3.0 LTR Turbo Diesel (1KZ-TE) with an auto. (Import)

It runs really well. I have a vibration that shakes the car when at idle in drive. When in neutral its fine.
If I raise the revs a bit its gone. The idle is about 750 rpm.

What could it be?

Any help much appreciated.....

a jap hiding in the back

he knocks his head every time you put it into drive

heavey duty oil stabilizer

Have you Checked your engine mounts Is one broken ??