About to rebuild diffs and gearbox/transfer case in my 1962 fj40 any info or ideas would be great
There must be a forum somewhere on the net dealing with these vehicules.
If you’ve never done this kind of work be VERY careful! With diffs you might need special tools and clearances are critical.
Why do they need rebuilding ?
The appearance of the drive train on those old Toyotas is very similar to 1950s and 1960s US 4 wheel drives built by Jeep and International Harvester and it is likely that they reverse engineered everything. If so, and if the housings and gears, etc are not damaged all that will be necessary is bearings and seals which can be easily matched at a good industrial supplier that could actually measure the old pieces and match new pieces to replace them. You might find that the king pin function is replaced with knuckles riding on tapered roller bearings on the axle ball housings with a stack of shims under and over the bearing end cap to be used as needed to set free play.
I definitely advise getting a good shop manual to follow.
Both are somewhat complex repair procedures. Both will require some special tools and the mechanical ability to sort out directions in a good (preferably factory) shop manual.
None of us know the limits of your mechanical skills. There’s far more to either one of those than simply replacing a handful of bearings and calling it good.
No offense, but if you’re asking around on how to rebuild diffs,transmissions, and transfer cases, it’s sort of a situation where “if you have to ask how to do it, then you probably shouldn’t be attempting it”.