We use VA in all sorts of industrial electrical motor driven rotating equipment but I've not seen it used in IC engines. There are a number of reasons why not. Perhaps a prox probe on the shaft would work if somebody could figure out how to install one. I'm sure smarter people than me are on it.
As far as predictive technology goes there is of course oil analysis and the IMS Guardian (is it still available?) although I can't say how well that works. I may end up using oil sampling and filter inspections myself. It can be done cheaply.