Being a diesel-head, I have to weigh in here. I was never a fan of the ZD30 motor on in the Patrol, however over the years I have grown a little love for them ( Just a little ....hahahaha)
That motor is quite a powerful engine and does without a doubt work well in a Patrol..... however.... there are certain things that MUST be done to ensure one can reach the Km lifespan of a TD42 and TB42 / TB45 / TB48 motors. The new ( post 2004 models were supposedly sorted... that's when manufactured, not date of registration
!!!! ). But even on the new ( post 2004 ) models an EGT gauge the MOST IMPORTANT piece of equipment that should be fitted. This is often not done buy owners who are not e know, and hence the handgrenade is born. Yes this is an issue that Nissan should have resolved on the older models and and and and.... but this never happened.
If I was going to buy a running 3.0 diesel Patrol, I would first of all try to get it for as cheap as possible, to allow me to spend a bit of money opening the motor up. If the motor is running, there is no repair cost. This way one can inspect the pistons for any issues. I would probably buy new pistons, rings and bearings, as these costs would be fairly cheap, refit everything back with a new high quality ( not an "el cheapo" )head gasket, flush the radiator and replace with genuine Nissan antifreeze/coolant, and Bob's ya Auntie, you have basically a brand new motor.
Before driving anywhere, I would block the EGT etc and do the various cheap modifications that are well documented on the forum, and drive that Patrol for many many Km. Those ZD motors can be serviced super easy much like the petrol Patrols ( 10 000Km - although I think they say 15 000Km in the book, but I would keep it at a max of 10 000 ) can and for cheaper. and you get great fuel savings and the only place the petrol Patrol will beat you is in the big sand dunes.
Don't get me wrong, I do love the sound and power of a 6 cylinder 4.8, but even my 4.2 turbo diesel will run well with a 4.5 and a 4.8 ( execpt the 4.8 on top speed )and be more fuel efficient. If you look after the vehicle from scratch, then you won't have the massive costs of repairing a diesel engine...... not that repairing a petrol engine is really much cheaper.....
So back to topic.... If you can get it for a damn good price, and spend the money top ensure a brand new motor will be the end result with looooooooong km ahead, then I say go for it. The petrol heads here on the forum will say that the petrol is better, and the diesel heads will say that the diesel is better. An opinion is like an ...... never mind....hahaha.... we are all passionate about our beasts
You must choose what Patrol YOU want and like