Another fellow ZD30 owner here. These are GREAT engines so long as you keep a clean MAF sensor (Every service, spray it) and keep an eye on boost levels once the EGR is blanked.
Mine has 345,000 on the clock, frequently has a 2 ton trailer hooked up to it and zero issues from the engine over the last 260,000k.
FYI, the turbo is a VNT so boost fluctuations are from my experience, caused by the control solenoid sticking - again, a quick squirt of cleaner spray is awesome here.
My peak boost spikes to 24PSI before dropping to a steady 22PSI and EGT's don't ever seem to climb to an area of concern.
It's a worthwhile job to pull the inlet manifold and give it a clean, the EGR has a habit of sooting it up and results in Cyl #3 running excessively rich - This is the reason they were nicknamed the 'Hand Grenade'. Unfortunately there is no knowing that it's running like this until either, A. An inspection/clean of the intake manifold or, B. Boom!
