My question is: What are your thoughts, and did I make a mistake doing this?? I was never an advocate of oil additives and this is the first time in its 149,000 mile life attempting it. The engine has been very well maintained/oiled with synthetics. I had a persistent lifter noise that was going outside the "20 minute parameter" and continued to constant. Now faced with a 3000.00 or so lifter overhaul I had to think and make at least an effort to try a "German made" product set of flush and treat. The flush alone did not change anything but when doing the treatment the change was evident after driving cycling/lugging and revving the engine! Well, I am quite surprised to have a silent lifter engine. My observations are repeatable starts in all temperatures/conditions and everyday hot .I have been enjoying this noiseless engine for a week so far. Will follow up...Thanks in advance for any info!