Try panhard rod bushes, get someone to shake steering while you look underneath.
I had the same symptoms but at 90kmh, they were the culprit.

 

thank you i will try this.

 

Bearing shocks kingpins. Steering arm. Theres lots of reasons for it. On my mq it comes n goes depending on how much grease is left in the fittings. I really should pull everything out n replace it but works for now. Its not daily driven so not on list of **** to do. Check everything grease everything n see how it goes.

 

hello
i do not have anymore the problem.here is a small note haw i did it.
05.11.2023 258.701 km
changed the left front wheel bearing (a liitle but of play) and the locking washer nissan part 43233-45460 was completly broken
result : no good problem still the same
08.01.2024 259.120 km
the big job i have replaced following parts
stabilizing rod 2 rubber bush nissan part 54613-g9600
complete new 2 small stabilizing rod nissan 54611-g9891
front leaf spring front side 4 rubber bush nissan 55045-g9600
2 metal bush nissan 55074-00900 ??
rear side 2 metal bush 55045-g9500
steering rod nissan 48680-g9501
track rod nissan 48520-g9502
2 ball joint on the track rod tube 48570-g9501
result : no vibrations any more problem solved
i have added the original part nissan numbers however nissan does not supply them any more but it is a big help when you are looking on sites like autodoc or winparts....
my car : nissan patrol 260 year 06/1991

i have 2 good pages with my notes coming from the original service manuel but i have problem to publish them.if anybody can help ...i share them with the comunity