I Used Syntec Synthetic 5-w30 in my Hemi on my last oil change.It has 34,000 miles on it, and it started knocking Cold or Hot it didn't matter. I switched to my personal favorite, Castrol GTX.5-w30- and the tapping went away almost imediately.
Iv'e used Castrol GTX in my Harleys for a long time without a problem- I use 20-w50 in the Transmission- and Primary chain as well as the Motor.. I won't pay Harley Davidson $6.00 a quart for oil because it has Harley Davidson on the bottle. It's Valvaline..

 

Oils designated for these newer vehicles in the last few years are now designed to be *******ly sludge proof.They are designed to be used up to 10,000 miles.Most all the manufacturers are now going by oil life monitoring systems.Not miles.

 

O.K. Then go to the Dollar store , Get some of that great $2.00 stuff, and throw it in youre new Hemi- OR Caddy or Go Cart ..80k miles later I'll show you enough wax to make candles..If you like them oil scented..I don't care what kind of monitoring system they go by the average american uses miles, and all oils are not and never will be created equal. Differant companies use differant methods and it changes the the way it burns- and lubricates..Some re-cycle oil and use wax to make up the vescostity, When it melts -it sticks, to everything. Creating sludge..It still happens.

 

run any oil to 80000 miles and it will sludge hello.

 

Whatever.If the oil is the correct rating for these newer engines it dosen't matter if it cost 2 cents.It won't sludge like oil of yester year. But whatever. The world is still flat and tomatoes are poisonous.

 

all that is, is the timing chain making noise it is nothing to worry about the timing chain tensioners are aided by oil pressure and the ticking noise you are hearing is your timing chains on your timing chain guides nothing to worry about unless it gets very very loud like rod knock loud haha

 

what ever dude, you`re the expert

 

He is correct on 0-20, I am from NY too, and lived up in Blue Mountain Lake..20-30 below at night...we ran 0-40, and 0-30 in our cars all the time. If you look at the pour rates it has a little better pour/freeze rate which allows for better flow. Call Mobil oil, same as running 5-20 will not void warranty. This oil came out for extremely cold environments, once warmed up it is still a 20 weight grade...