[brian_]

If you want to follow the easiest approach of keeping the original style of 4WD system, and the existing transfer case doesn't fit the Toyota hybrid transmission (and it probably won't), then another Toyota transfer case might work, or a custom adapter may be possible, or a divorced transfer case configuration might be a good solution.

The Ford "crate motor" appears to be a Mach-E rear drive unit, so it is like salvaging a unit from a Mach-E or any other typical EV... and it isn't really available anyway. Any available salvaged EV drive unit has the challenge of not fitting with the design of this vehicle at all.

 

[brian_]

The dimensions need to be checked, but I wouldn't assume that a transmission designed to fit a car the size of the Lexus GS would be large compared to the transmission in the Montero. If "too big" was intended to refer to power or torque output, I wouldn't expect a transfer case that can handle the output of a 3L engine (torque multiplied by first gear of the stock transmission) having a problem with the output of a Toyota hybrid transmission. Actual numbers should be checked before final decisions.

The low range in a traditional 4WD can provide more torque to the wheels at low speed than would otherwise be available in the lowest gear; that may not be an issue, depending on the motor choice. It can also simply allow lower speed for extreme conditions without stalling the engine, which is not an issue.

 

[brian_]

Starting with a small battery and adding later is tough. If you design the battery as a set of parallel strings you can add strings over time, but your BMS has to manage multiple strings. Alternatively you can design for a final battery voltage when it is complete and have a fraction of that to start, adding in series to complete it; that will probably mean inadequate performance with the initial battery size and voltage. If you use individual prismatic cells you could rebuild it for more cells in parallel to expand, but that's a lot of rework.

Some production EVs are available with a choice of battery sizes, but they normally designed to the same (or at least close) overall voltage, and it's generally not possible to start with the smaller option and just add modules to get the later option.

 

[brian_]

The 281hp crate motor sounds great I wonder How much it will cost?

The Ford "crate motor" is not expensive, but it's not just a motor - it's a complete drive unit of motor with reduction gearing and differential. How would you use that in a Montero?

If I understand correctly, low range is not necessary with an electric motor?

Low range isn't necessary with most engines for most purposes, either. It's a matter of determining how much torque will be available to the wheels at low speed, and comparing that to what you need.

So maybe the L110f will work? Wouldn't this be the easiest way?

In some ways this hybrid transmission/drive unit is an easy way to go, because it will fit in the space originally occupied by the transmission, with it and the battery replacing both the engine and the transmission.

Do you think it would out perform a Leaf motor hooked up to the original trans?

That's very dependent on details... is it is a stock Leaf drive unit, or with a modified controller and/or inverter? Which Leaf drive unit... 80 kW (came in cars with 24 kWh and 30 kWh batteries), 110 kW (comes in cars with 40 kW battery), or 160 kW (comes in cars with 62 kWh battery)? Is the L110 modified to use MG1 as well as MG2? Would the transmission be shifted to optimize Leaf motor output?

At the most basic level, MG2 of the L110 is rated at higher power than the common (80 kW) Leaf motor, but the transmission could keep the Leaf motor up in speed to make more power available at low road speed.

When you say "fit" do you mean fiscally?

No, I mean physically and mechanically... but which "fit" comment are you asking about?