I just found a movie of my first diesel/electric hybrid vehicles

My employer used diesel/electric trucks but added an all electric option to speed them up.

Quicktime Movie

The manager's thinking was that the trucks could only go uphill at 7 MPH on diesel, and could go 11 MPH on electric. What the drivers actually found was that they could get 13 MPH using both at once, so productivity doubled. Pollution was halved, as the trucks only spent 1/2 the time going uphill, but the same amount of time on the level ground.

 

No, but you can put 190 tons in the back, even at 1/10 of an ounce per ton of gold that is quite a bit.

They do make tanker versions.