So my big dilemma comes down to transfer case options since I have a very awesome rear end setup already, which is set up with Toyota v6/full floater parts and utilizes the less than common passenger side Samurai offset...
Land Cruiser transfer cases utilize passenger side offsets front and rear...
1985 or 1990+ saw the availability of the sought after R151F transmission with a special rear housing and transfer case mating shaft/coupler to run the "splitcase" style of 1980+ Land Cruiser transfer cases... I have a line on one of these used, missing the transfer case, and with 5th gear issues.it has the broader AX15 2nd-3rd gears (2.33 2nd) and with a deeper crawler 1st gear of 4.31:1 vs the R150/AX15 at 3.83:1. W56 has similar 5th to the R151F/R150F @ .83 od, but a middleground deeper 3.95:1 1st than the AX15/R150F.
This sounds like a no brainer here! I may have to import an HZJ73 or HZJ79 transfer case, however or other J7# variants. I'm not sure if the 1980 - 1990 us version splitcase transfer cases are 100% compatible, although the outside pattern of the gasket is looking to be identical, there is a divider plate casting across the middle on the newer versions that may isolate the oil lubricating the rear bearings to the top half of the rear trans case housing, I will have to investigate this further, I'm not really sure how the lubrication works there.
The newer 1990's/2000's 70 series Land Cruiser transfer cases come in many versions that are full-time 4 wheel drive with a viscous coupler center differential setup as well. If I were driving in the snow a lot, this would definitely be a plus, as I would not have to worry about switching in and out of 4 wheel drive when I hit dry pavement, but also is a big detractor from the fuel economy, so I will probably just stay with a selectable transfer case high / low setup.
there are deeper gears available for these cases, but the gear sets will also affect the high range slightly. Swapping the ax15 5th gear with a small spacer turned up on a lathe will help recover that, and also the r154 transmission has a much deeper overdrive, although I had read someone saying that it works out to be less have a sleepover drive when you figure in the cluster ratio? This I am not educated on. In the same thread, someone said the gears from the infamous Aisin R154 Hino/Dyna transmission (donor for the 5:1 1st gear cluster to fit into R150's) would give the lowest numerical output ratio. The R154 is listed as .76:1 if I recall.
