This was something I learned many years ago back on the farm. In a gasser, if you have lifters making noise...has to be the right kind of noise to work... if you replaced one quart of oil with a quart of ATF, the detergent in the ATF would aid in cleaning the lifters and the noise would go away. We didn't have any vehicles with auto trans so that just meant a trip to town for us(YEAH)
Back in the 70's, I had a 66 Fairlane GT with a 390 that started having some lifter chatter. A friend was over when I dumped in ATF in my oil along with a filter change to lower my oil down the quart of space I needed. He lives in TN now and still calls when he has a problem. I'm no mechanic but he thinks I can fix anything.

Don't ask me about "the right kind of noise". I can't answer that and I can't imitate the sound either. Just something that you know when you hear it and can tell that it's not a bent push rod.