H55f, h41 gearbox service/ recommend oil

[Gazzo]

Hi everyone, I'm new to the forum
Between myself, my brother and my dad we own 2 fj45s and one hj47 and all three are due for a service.
The plan is gearbox, engine, diffs and especially the brakes.
Though just to be sure what oil is recomended for the gearboxes? The 45s have the stock 4 speeds and the 47 has a h55f gearbox currently getting rebuilt which was originally removed ftom an 84 fj45.
Any help much appreciated.

 

[Gazzo]

And some pics

 

[4Cruisers]

I had the same question for the new H55f going into my '86 FJ60 project vehicle. Output Shaft posted about using Mobil Delvac Synthetic Transmission Fluid SAE 50 (see Post #50):

some h55f and split case tech