I had a CJ7 with a 3CT. I have used to two 1Cs and also a 2C.
If the engine is not burning oil, the level is not dropping on the dip stick and it is not giving you trouble in the morning starting cold; it is just fine.
Just make sure you change the oil every 2000 km and keep a close eye and ear for any thing or noise, strange.
These toyota diesel engines are built to last, this engine will surprise you with the reliability and durability.