Shortly after I bought my truck last summer it developed some weird ticking noise. I posted the problem here: https://forum.ih8mud.com/diesel-tech-24-volts-systems/242027-my-hdj81-saga.html The noise was definitely coming from the crankcase general area. I have confirmed with a stethoscope, and two other mechanic shops confirmed that it is coming from that area. After the oil analysis came O.K., I didn't really bother with the noise. I drove ~ 10,000 km since then without a problem. However, with time the noise got more frequent and louder. Now, I have removed the ACSD afew days ago due to abnormally high RPM. Read my post here: https://forum.ih8mud.com/diesel-tech-24-volts-systems/266555-acsd-mysterious-device.html After a few days driving, the ticking noise is almost gone!! It is still there to some extent, but fainter and very less frequent.. The ticking noise was DEFINITELY not coming from the ACSD as confirmed by 3 different persons.. Isn't it weird??