Ron is correct,
Me personally,I won't run WMO in anything except our WMO heater at work,even with multiple pass filtering it still leaves micron sized particles in,plus just filtering will not weed out the acids and other liquid contamanants in the WMO.
The Mack injection pump differs from the Multi and NHC250 Cummins,the Multi uses just 1 plunger for injection and a distruibter type system to deliver it to each individual cylinder at the proper time,the PT system on the Cummins basically uses a gear type pump and throttling orifice to deliver fuel to the injectors via a passage drilled into the cylinder heads,the injectors are actuated manually from lobes on the camshaft and speed/power is regulated by the pressure at which fuel is delivered.
Both systems can cope with somewhat more viscious fluids than the injection system on the Mack.
The Mack engine uses a American Bosch APE series inline pump(similar to the IP on a 8.3C series or older 5.9 B series Cummins) it has a plunger and delivery sleeve for each individual cylinder,all are actuated by a camshaft inside the lower section of the IP.
Fuel delivery in the Mack IP is controlled by rotating a delivery sleeve that surrounds each plunger,this is accomplished by a toothed shaft linked to the governer at the rear.
Basically it boils down to the WMO would have to be thinned so much to properly work in the IP that all it's lubricating qualities would be washed out,it would cause excessive heat and galling of the plungers and shortly a worn out IP.
And at $1800 to $2000 for a rebuild for the pump and about $150 ea for the injectors, basically $2900 for a new fuel system that,depending on how much you drive the truck and how far each trip was ,could be as much as every year for a rebuild.
Plus given the rarity of Mack powered MVs and parts,prices are bound to keep going up.
Just my