Here's several threads on oil consumption, theories of what causes the problem, engine failure, polls, experience, etc... Might help you decide on whether it's the pistons, or better to rebuild or replace with an Axiom engine.
Several theories on Isuzu design defect in rings that causes oil consumption:
http://www.vehicross.info/forums/sho...rand+pcv+valve
http://vehicross.info/forums/showthr...E+FAILURE+POLL
http://vehicross.info/forums/showthr...E+FAILURE+POLL
http://vehicross.info/forums/showthr...ngine+oil+poll
http://vehicross.info/forums/showthr...184#post166184
http://www.vehicross.info/forums/sho...light=axiom+DI
http://www.vehicross.info/forums/sho...light=axiom+DI
http://vehicross.info/forums/showthr...ght=iamironman
Here's the thread from Iamironman...
http://www.vehicross.info/forums/sho...ght=built+2000
http://www.vehicross.info/forums/sho...ine+swap+axiom
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