Read this, note polls, they are public, meaning 100's of respected ram members took part in testing because hemi tick is a scourge on ram owners. In the beginning we tested many oils and combo's, but as time passed most of us only went with what worked best, note the poll date was 8 years into our testing. Early results are in this thread. It is really about formula and not brand, there is a scientific reason why redline stops knocking lifters in the bore and other oils don't.
Hemi tick is a cam lobe pushing a lifter into the bore but the bore is not properly lubricated. As it turns out the heavy EP additives and base oils in redline compensate for the deficiency in oil more then all other choices with an 80% success rate. Now, a small number of those benefit from viscosity increases, it just depends on how bad the tick is. The worst the tick, the more heavy additives and saturated base oils work, the lesser the tick the more a heavy viscosity will work. In many cases it was 5w20 that killed the tick over any other oil, but some rams were more successful with 5w30, it is those trucks with lesser ticks then others. The greater the pressure, the more the conditions for EP additives to thrive.