Giz and Gus, the oil drain hole issue is one that I have heard before, and them plugging up is one of the reasons why some of these engines grenade themselves at a relatively young age. I don't think mine is an oil starvation issue, though the engine has always used a LOT of oil (3/4 of a quart of oil every 300-350 miles). I've always stayed on top of it and she's run like a champ up until now. From the research I have done I believe that there is something going on with the piston, rings, or cylinder itself. Maybe that is an oil drain hole issue though.
Leak down test on Friday will tell a little bit more about what's going on.
I had also heard the same things about the Axiom engines. The direct injection engine won't fit in our VX's due to them using a different transmission, and the Axiom engine's that would fit in our VX's came from and '02-'03 Axiom with an "X" as the eighth digit in the VIN. I think the "X" denoted the four wheel/all wheel drive option in the Axiom which meant it was basically using our transmission and transfer case.
If a rebuilt engine will solve the oil burning issue that would be great. Dave, do you have any contact information for Jerry Lemond? I've heard of this fabled Isuzu guru, and it would be great to talk to/ email with him to get his opinion on engine re-builders, engine options, things to look out for, etc.