Originally Posted by SRT-6 Steve
My point was that from my experience as well as a local person last year with a N/A both had the same issue which was a loud know that pasted for about 5 seconds right after start up as well as a constant but softer tap during idle. They were gone once the correct oil was used. I am in no way suggesting this will replace a mechanical issue but he needs an oil change and already mentioned it has the incorrect weight in it. It is worth a try before spending $ with a mechanic as it needs done anyway.
I have been involved with cars for over 30 years and even though I may not attempt some of the projects that a few on here including yourself are working on, there are some things that don't need a whole lot of explaining and when I see a comment like oil is oil, what the heck!!!
I am sorry if you thought I was disagreeing with you. I agree, but forget that many people don't work on their own cars. Since he said knocking and not tapping I thought he may have a mechanical issue and the old screw driver to the ear is an easy way to find it and is free if you can do this. I don't agree that oil is oil or at least not for very long if you want your engine to last a long time.
I have only one use for dino oil and that is in a brand new engine. In a brand new engine synthetic is almost too good and it can take a long time for the rings to seat. Using dino oil for the first few hundred miles helps with engine break in and as soon as you no longer see any engine smoke from the exhaust it is time to put in the good stuff.