So this might be a good build... Either an AC or BLDC motor, maybe 40HP, in line w/ the trans, enough LiPO batteries for ten miles range (maybe rebuilt Prius battery pack), and a motor controller that supports regen, and plug-in charging.
Would need to fab up:
* Mounts for the motor
* Trans and driveline couplers, maybe w/ a bearing supporting the driveline coupler
* Battery pack & box
* Wiring and control circuitry
* Shorter driveline and any changes to rear axle to allow for different drive-line angle
A small battery pack like this & 40HP would enable doing small trips across town on electric as well as pulse and glide for longer trips... for freeway travel, we could spin up the gasoline engine every five miles for to push the truck and and to re-charge the battery pack, keeping load and efficiency higher, and then go full electric for the next few miles.
It would be nice if there were a seamless way to integrate the motor controls with the factory controls on the vehicle, but I think a good starting point would simply be a manual slider to tell the motor to accelerate, regen, or freewheel.
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