Guys, I plan on getting me a 5.2 ZJ with LPG (low pressure gas) conversion to run it for half the price of gasoline.
Are there any known problems with ZJs I should be looking at?

They are nice. A guy in another club wheels one the only problem he has it wont shift from 1st to 2nd. Don't know what tranny it has I know it's a 5 speed.

I love our (new to us) ZJ...rides like it's on air
Nice and comfy
I'd stay away if it has the full time all wheel drive....I've heard of problems with the "Viscous Coupler?" in the transfercase

Or you can always get it converted to a 242 or 231 transfercase...seen write ups about it

one of our guys wheels one on 33's and it does quite well.. he swapped in an ax-15 and 231 from a tj.. his is a 6 tho.. we used to have a v8 zj and it was a great truck too

I think LPG stands for Liquefied petroleum gas, but yes it is generally a cheaper and cleaner source of fuel, especially over in europe.

the 249 cases are notorious for failure if not taken care of (regular maintenance). the coupler between the front and the rear fails and it is expensive, but a 242 case swap is something to be done but does required complete case tear down.

the trans require regular maintenance if you wish for it to survive, I have seen plenty make it to the 300000+ KM mark (I have 3 currently that are almost at or above 300K)

Good vehicles if you take care of them, just like any other. and they ride nice

I for sure have to take a V8, the 4 liter seems to run too hot with LPG, heard from people with tons of overheating probs. A friend has one and even with new radiator, new high flow water pump and high flow fan it's not running too well... the V8 take it much easier without overheating.
If I want to convert to the 242 I have to take the XJ apart because you wont find any Jeeps in junk yards over here.
Yes, LPG also tranlates to liquified petroleum gas, but over here it's called low pressure gas because we also have high pressure gas called CNG (compressed natural gas).