[brian_]

The one aspect which jumps out at me, which is specific to your van, is that is your only vehicle. I think you need to plan on getting another vehicle for use during the conversion, because this is not going to be a quick process. Even with skills, equipment, and detailed planning in advance, it's unlikely to be a weekend project from driving into a garage and shutting off the engine for the last time, and driving a reliable electric vehicle out of that garage. Many conversion projects never get completed, and those that do routinely takes months to years as do-it-yourself projects.

Just for a reality check: for 100 mile range pushing a three-ton vehicle with big tires, you're going to need a battery with roughly the capacity of the enormous one in a Tesla. A brushed DC motor is the least efficient type you can readily get, which will increase the energy requirement compared to a modern EV motor. If you drive in urban conditions (stop-and-go), a brushed DC motor is not practical for regenerative braking, increasing the energy requirement further.

Can we assume that you want to keep the same axles, and stay 2WD?

 

[brian_]

I have plenty of other rides to use while my vans off line..

Good I guess I was either mixing up new people, or just misread your original post. Gotta slow down the reading...

Can you suggest some other motors with a higher efficiency?

Literally any other type of the same power level, likely AC (permanent magnet or induction).

The latest trend - if you want to be at the cutting edge of DIY EV conversions rather than the antique end of technology - is to use a motor from a production EV. Tesla Model S/X and Nissan Leaf are the common choices. This is a major project in electronics, so it may not be the way you want to go if that's not the type of work that you want to do.